diff --git a/modules/openapi-generator/src/main/java/org/openapitools/codegen/languages/PhpSymfonyServerCodegen.java b/modules/openapi-generator/src/main/java/org/openapitools/codegen/languages/PhpSymfonyServerCodegen.java
index 890431b9560..580e308f47a 100644
--- a/modules/openapi-generator/src/main/java/org/openapitools/codegen/languages/PhpSymfonyServerCodegen.java
+++ b/modules/openapi-generator/src/main/java/org/openapitools/codegen/languages/PhpSymfonyServerCodegen.java
@@ -386,7 +386,7 @@ public class PhpSymfonyServerCodegen extends AbstractPhpCodegen implements Codeg
         operations.put("controllerName", toControllerName((String) operations.get("pathPrefix")));
         operations.put("symfonyService", toSymfonyService((String) operations.get("pathPrefix")));
 
-        HashSet<CodegenSecurity> authMethods = new HashSet<>();
+        List<CodegenSecurity> authMethods = new ArrayList<CodegenSecurity>();
         List<CodegenOperation> operationList = (List<CodegenOperation>) operations.get("operation");
 
         for (CodegenOperation op : operationList) {
@@ -431,7 +431,11 @@ public class PhpSymfonyServerCodegen extends AbstractPhpCodegen implements Codeg
 
             // Add operation's authentication methods to whole interface
             if (op.authMethods != null) {
-                authMethods.addAll(op.authMethods);
+                for (CodegenSecurity am : op.authMethods) {
+                    if (!authMethods.contains(am)) {
+                        authMethods.add(am);
+                    }
+                }
             }
         }
 
diff --git a/samples/server/petstore/php-symfony/SymfonyBundle-php/Api/PetApiInterface.php b/samples/server/petstore/php-symfony/SymfonyBundle-php/Api/PetApiInterface.php
index 3d822e56f29..864fa5cd80f 100644
--- a/samples/server/petstore/php-symfony/SymfonyBundle-php/Api/PetApiInterface.php
+++ b/samples/server/petstore/php-symfony/SymfonyBundle-php/Api/PetApiInterface.php
@@ -43,15 +43,6 @@ use OpenAPI\Server\Model\Pet;
 interface PetApiInterface
 {
 
-    /**
-     * Sets authentication method api_key
-     *
-     * @param string $value Value of the api_key authentication method.
-     *
-     * @return void
-     */
-    public function setapi_key($value);
-
     /**
      * Sets authentication method petstore_auth
      *
@@ -61,6 +52,15 @@ interface PetApiInterface
      */
     public function setpetstore_auth($value);
 
+    /**
+     * Sets authentication method api_key
+     *
+     * @param string $value Value of the api_key authentication method.
+     *
+     * @return void
+     */
+    public function setapi_key($value);
+
     /**
      * Operation addPet
      *