diff --git a/modules/openapi-generator/src/main/resources/typescript-nestjs/api.service.mustache b/modules/openapi-generator/src/main/resources/typescript-nestjs/api.service.mustache
index ea7d0b00ee5..4f0f8dfa72a 100644
--- a/modules/openapi-generator/src/main/resources/typescript-nestjs/api.service.mustache
+++ b/modules/openapi-generator/src/main/resources/typescript-nestjs/api.service.mustache
@@ -103,7 +103,7 @@ export class {{classname}} {
 {{/queryParams}}
 
 {{/hasQueryParams}}
-        let headers = this.defaultHeaders;
+        let headers = {...this.defaultHeaders};
 {{#headerParams}}
         {{#isArray}}
         if ({{paramName}}) {
diff --git a/samples/client/petstore/typescript-nestjs-v6-provided-in-root/builds/default/api/pet.service.ts b/samples/client/petstore/typescript-nestjs-v6-provided-in-root/builds/default/api/pet.service.ts
index d05d59a3b0c..ba76f58877d 100644
--- a/samples/client/petstore/typescript-nestjs-v6-provided-in-root/builds/default/api/pet.service.ts
+++ b/samples/client/petstore/typescript-nestjs-v6-provided-in-root/builds/default/api/pet.service.ts
@@ -54,7 +54,7 @@ export class PetService {
             throw new Error('Required parameter pet was null or undefined when calling addPet.');
         }
 
-        let headers = this.defaultHeaders;
+        let headers = {...this.defaultHeaders};
 
         // authentication (petstore_auth) required
         if (this.configuration.accessToken) {
@@ -107,7 +107,7 @@ export class PetService {
         }
 
 
-        let headers = this.defaultHeaders;
+        let headers = {...this.defaultHeaders};
         if (apiKey !== undefined && apiKey !== null) {
             headers['api_key'] = String(apiKey);
         }
@@ -157,7 +157,7 @@ export class PetService {
             queryParameters['status'] = status.join(COLLECTION_FORMATS['csv']);
         }
 
-        let headers = this.defaultHeaders;
+        let headers = {...this.defaultHeaders};
 
         // authentication (petstore_auth) required
         if (this.configuration.accessToken) {
@@ -207,7 +207,7 @@ export class PetService {
             queryParameters['tags'] = tags.join(COLLECTION_FORMATS['csv']);
         }
 
-        let headers = this.defaultHeaders;
+        let headers = {...this.defaultHeaders};
 
         // authentication (petstore_auth) required
         if (this.configuration.accessToken) {
@@ -252,7 +252,7 @@ export class PetService {
             throw new Error('Required parameter petId was null or undefined when calling getPetById.');
         }
 
-        let headers = this.defaultHeaders;
+        let headers = {...this.defaultHeaders};
 
         // authentication (api_key) required
         if (this.configuration.apiKeys["api_key"]) {
@@ -293,7 +293,7 @@ export class PetService {
             throw new Error('Required parameter pet was null or undefined when calling updatePet.');
         }
 
-        let headers = this.defaultHeaders;
+        let headers = {...this.defaultHeaders};
 
         // authentication (petstore_auth) required
         if (this.configuration.accessToken) {
@@ -348,7 +348,7 @@ export class PetService {
 
 
 
-        let headers = this.defaultHeaders;
+        let headers = {...this.defaultHeaders};
 
         // authentication (petstore_auth) required
         if (this.configuration.accessToken) {
@@ -416,7 +416,7 @@ export class PetService {
 
 
 
-        let headers = this.defaultHeaders;
+        let headers = {...this.defaultHeaders};
 
         // authentication (petstore_auth) required
         if (this.configuration.accessToken) {
diff --git a/samples/client/petstore/typescript-nestjs-v6-provided-in-root/builds/default/api/store.service.ts b/samples/client/petstore/typescript-nestjs-v6-provided-in-root/builds/default/api/store.service.ts
index cb919215836..cadb5a9048c 100644
--- a/samples/client/petstore/typescript-nestjs-v6-provided-in-root/builds/default/api/store.service.ts
+++ b/samples/client/petstore/typescript-nestjs-v6-provided-in-root/builds/default/api/store.service.ts
@@ -53,7 +53,7 @@ export class StoreService {
             throw new Error('Required parameter orderId was null or undefined when calling deleteOrder.');
         }
 
-        let headers = this.defaultHeaders;
+        let headers = {...this.defaultHeaders};
 
         // to determine the Accept header
         let httpHeaderAccepts: string[] = [
@@ -82,7 +82,7 @@ export class StoreService {
     public getInventory(): Observable<AxiosResponse<{ [key: string]: number; }>>;
     public getInventory(): Observable<any> {
 
-        let headers = this.defaultHeaders;
+        let headers = {...this.defaultHeaders};
 
         // authentication (api_key) required
         if (this.configuration.apiKeys["api_key"]) {
@@ -122,7 +122,7 @@ export class StoreService {
             throw new Error('Required parameter orderId was null or undefined when calling getOrderById.');
         }
 
-        let headers = this.defaultHeaders;
+        let headers = {...this.defaultHeaders};
 
         // to determine the Accept header
         let httpHeaderAccepts: string[] = [
@@ -158,7 +158,7 @@ export class StoreService {
             throw new Error('Required parameter order was null or undefined when calling placeOrder.');
         }
 
-        let headers = this.defaultHeaders;
+        let headers = {...this.defaultHeaders};
 
         // to determine the Accept header
         let httpHeaderAccepts: string[] = [
diff --git a/samples/client/petstore/typescript-nestjs-v6-provided-in-root/builds/default/api/user.service.ts b/samples/client/petstore/typescript-nestjs-v6-provided-in-root/builds/default/api/user.service.ts
index a9f4108418d..7cac2f8bf53 100644
--- a/samples/client/petstore/typescript-nestjs-v6-provided-in-root/builds/default/api/user.service.ts
+++ b/samples/client/petstore/typescript-nestjs-v6-provided-in-root/builds/default/api/user.service.ts
@@ -53,7 +53,7 @@ export class UserService {
             throw new Error('Required parameter user was null or undefined when calling createUser.');
         }
 
-        let headers = this.defaultHeaders;
+        let headers = {...this.defaultHeaders};
 
         // authentication (api_key) required
         if (this.configuration.apiKeys["api_key"]) {
@@ -98,7 +98,7 @@ export class UserService {
             throw new Error('Required parameter user was null or undefined when calling createUsersWithArrayInput.');
         }
 
-        let headers = this.defaultHeaders;
+        let headers = {...this.defaultHeaders};
 
         // authentication (api_key) required
         if (this.configuration.apiKeys["api_key"]) {
@@ -143,7 +143,7 @@ export class UserService {
             throw new Error('Required parameter user was null or undefined when calling createUsersWithListInput.');
         }
 
-        let headers = this.defaultHeaders;
+        let headers = {...this.defaultHeaders};
 
         // authentication (api_key) required
         if (this.configuration.apiKeys["api_key"]) {
@@ -188,7 +188,7 @@ export class UserService {
             throw new Error('Required parameter username was null or undefined when calling deleteUser.');
         }
 
-        let headers = this.defaultHeaders;
+        let headers = {...this.defaultHeaders};
 
         // authentication (api_key) required
         if (this.configuration.apiKeys["api_key"]) {
@@ -227,7 +227,7 @@ export class UserService {
             throw new Error('Required parameter username was null or undefined when calling getUserByName.');
         }
 
-        let headers = this.defaultHeaders;
+        let headers = {...this.defaultHeaders};
 
         // to determine the Accept header
         let httpHeaderAccepts: string[] = [
@@ -276,7 +276,7 @@ export class UserService {
             queryParameters.append('password', <any>password);
         }
 
-        let headers = this.defaultHeaders;
+        let headers = {...this.defaultHeaders};
 
         // to determine the Accept header
         let httpHeaderAccepts: string[] = [
@@ -308,7 +308,7 @@ export class UserService {
     public logoutUser(): Observable<AxiosResponse<any>>;
     public logoutUser(): Observable<any> {
 
-        let headers = this.defaultHeaders;
+        let headers = {...this.defaultHeaders};
 
         // authentication (api_key) required
         if (this.configuration.apiKeys["api_key"]) {
@@ -352,7 +352,7 @@ export class UserService {
             throw new Error('Required parameter user was null or undefined when calling updateUser.');
         }
 
-        let headers = this.defaultHeaders;
+        let headers = {...this.defaultHeaders};
 
         // authentication (api_key) required
         if (this.configuration.apiKeys["api_key"]) {
diff --git a/samples/client/petstore/typescript-nestjs-v8-provided-in-root/builds/default/api/pet.service.ts b/samples/client/petstore/typescript-nestjs-v8-provided-in-root/builds/default/api/pet.service.ts
index a9edbe9d200..851eb41148c 100644
--- a/samples/client/petstore/typescript-nestjs-v8-provided-in-root/builds/default/api/pet.service.ts
+++ b/samples/client/petstore/typescript-nestjs-v8-provided-in-root/builds/default/api/pet.service.ts
@@ -55,7 +55,7 @@ export class PetService {
             throw new Error('Required parameter pet was null or undefined when calling addPet.');
         }
 
-        let headers = this.defaultHeaders;
+        let headers = {...this.defaultHeaders};
 
         // authentication (petstore_auth) required
         if (this.configuration.accessToken) {
@@ -108,7 +108,7 @@ export class PetService {
         }
 
 
-        let headers = this.defaultHeaders;
+        let headers = {...this.defaultHeaders};
         if (apiKey !== undefined && apiKey !== null) {
             headers['api_key'] = String(apiKey);
         }
@@ -158,7 +158,7 @@ export class PetService {
             queryParameters['status'] = status.join(COLLECTION_FORMATS['csv']);
         }
 
-        let headers = this.defaultHeaders;
+        let headers = {...this.defaultHeaders};
 
         // authentication (petstore_auth) required
         if (this.configuration.accessToken) {
@@ -208,7 +208,7 @@ export class PetService {
             queryParameters['tags'] = tags.join(COLLECTION_FORMATS['csv']);
         }
 
-        let headers = this.defaultHeaders;
+        let headers = {...this.defaultHeaders};
 
         // authentication (petstore_auth) required
         if (this.configuration.accessToken) {
@@ -253,7 +253,7 @@ export class PetService {
             throw new Error('Required parameter petId was null or undefined when calling getPetById.');
         }
 
-        let headers = this.defaultHeaders;
+        let headers = {...this.defaultHeaders};
 
         // authentication (api_key) required
         if (this.configuration.apiKeys["api_key"]) {
@@ -294,7 +294,7 @@ export class PetService {
             throw new Error('Required parameter pet was null or undefined when calling updatePet.');
         }
 
-        let headers = this.defaultHeaders;
+        let headers = {...this.defaultHeaders};
 
         // authentication (petstore_auth) required
         if (this.configuration.accessToken) {
@@ -349,7 +349,7 @@ export class PetService {
 
 
 
-        let headers = this.defaultHeaders;
+        let headers = {...this.defaultHeaders};
 
         // authentication (petstore_auth) required
         if (this.configuration.accessToken) {
@@ -417,7 +417,7 @@ export class PetService {
 
 
 
-        let headers = this.defaultHeaders;
+        let headers = {...this.defaultHeaders};
 
         // authentication (petstore_auth) required
         if (this.configuration.accessToken) {
diff --git a/samples/client/petstore/typescript-nestjs-v8-provided-in-root/builds/default/api/store.service.ts b/samples/client/petstore/typescript-nestjs-v8-provided-in-root/builds/default/api/store.service.ts
index 947bae1be17..6b35126e5ba 100644
--- a/samples/client/petstore/typescript-nestjs-v8-provided-in-root/builds/default/api/store.service.ts
+++ b/samples/client/petstore/typescript-nestjs-v8-provided-in-root/builds/default/api/store.service.ts
@@ -54,7 +54,7 @@ export class StoreService {
             throw new Error('Required parameter orderId was null or undefined when calling deleteOrder.');
         }
 
-        let headers = this.defaultHeaders;
+        let headers = {...this.defaultHeaders};
 
         // to determine the Accept header
         let httpHeaderAccepts: string[] = [
@@ -83,7 +83,7 @@ export class StoreService {
     public getInventory(): Observable<AxiosResponse<{ [key: string]: number; }>>;
     public getInventory(): Observable<any> {
 
-        let headers = this.defaultHeaders;
+        let headers = {...this.defaultHeaders};
 
         // authentication (api_key) required
         if (this.configuration.apiKeys["api_key"]) {
@@ -123,7 +123,7 @@ export class StoreService {
             throw new Error('Required parameter orderId was null or undefined when calling getOrderById.');
         }
 
-        let headers = this.defaultHeaders;
+        let headers = {...this.defaultHeaders};
 
         // to determine the Accept header
         let httpHeaderAccepts: string[] = [
@@ -159,7 +159,7 @@ export class StoreService {
             throw new Error('Required parameter order was null or undefined when calling placeOrder.');
         }
 
-        let headers = this.defaultHeaders;
+        let headers = {...this.defaultHeaders};
 
         // to determine the Accept header
         let httpHeaderAccepts: string[] = [
diff --git a/samples/client/petstore/typescript-nestjs-v8-provided-in-root/builds/default/api/user.service.ts b/samples/client/petstore/typescript-nestjs-v8-provided-in-root/builds/default/api/user.service.ts
index 6f3c97b86e6..f5e7a5ff5c5 100644
--- a/samples/client/petstore/typescript-nestjs-v8-provided-in-root/builds/default/api/user.service.ts
+++ b/samples/client/petstore/typescript-nestjs-v8-provided-in-root/builds/default/api/user.service.ts
@@ -54,7 +54,7 @@ export class UserService {
             throw new Error('Required parameter user was null or undefined when calling createUser.');
         }
 
-        let headers = this.defaultHeaders;
+        let headers = {...this.defaultHeaders};
 
         // authentication (api_key) required
         if (this.configuration.apiKeys["api_key"]) {
@@ -99,7 +99,7 @@ export class UserService {
             throw new Error('Required parameter user was null or undefined when calling createUsersWithArrayInput.');
         }
 
-        let headers = this.defaultHeaders;
+        let headers = {...this.defaultHeaders};
 
         // authentication (api_key) required
         if (this.configuration.apiKeys["api_key"]) {
@@ -144,7 +144,7 @@ export class UserService {
             throw new Error('Required parameter user was null or undefined when calling createUsersWithListInput.');
         }
 
-        let headers = this.defaultHeaders;
+        let headers = {...this.defaultHeaders};
 
         // authentication (api_key) required
         if (this.configuration.apiKeys["api_key"]) {
@@ -189,7 +189,7 @@ export class UserService {
             throw new Error('Required parameter username was null or undefined when calling deleteUser.');
         }
 
-        let headers = this.defaultHeaders;
+        let headers = {...this.defaultHeaders};
 
         // authentication (api_key) required
         if (this.configuration.apiKeys["api_key"]) {
@@ -228,7 +228,7 @@ export class UserService {
             throw new Error('Required parameter username was null or undefined when calling getUserByName.');
         }
 
-        let headers = this.defaultHeaders;
+        let headers = {...this.defaultHeaders};
 
         // to determine the Accept header
         let httpHeaderAccepts: string[] = [
@@ -277,7 +277,7 @@ export class UserService {
             queryParameters.append('password', <any>password);
         }
 
-        let headers = this.defaultHeaders;
+        let headers = {...this.defaultHeaders};
 
         // to determine the Accept header
         let httpHeaderAccepts: string[] = [
@@ -309,7 +309,7 @@ export class UserService {
     public logoutUser(): Observable<AxiosResponse<any>>;
     public logoutUser(): Observable<any> {
 
-        let headers = this.defaultHeaders;
+        let headers = {...this.defaultHeaders};
 
         // authentication (api_key) required
         if (this.configuration.apiKeys["api_key"]) {
@@ -353,7 +353,7 @@ export class UserService {
             throw new Error('Required parameter user was null or undefined when calling updateUser.');
         }
 
-        let headers = this.defaultHeaders;
+        let headers = {...this.defaultHeaders};
 
         // authentication (api_key) required
         if (this.configuration.apiKeys["api_key"]) {