diff --git a/modules/openapi-generator/src/main/resources/kotlin-spring/api_test.mustache b/modules/openapi-generator/src/main/resources/kotlin-spring/api_test.mustache
index ad8b33bfbff..8cca99bb5b5 100644
--- a/modules/openapi-generator/src/main/resources/kotlin-spring/api_test.mustache
+++ b/modules/openapi-generator/src/main/resources/kotlin-spring/api_test.mustache
@@ -27,7 +27,7 @@ class {{classname}}Test {
     @Test
     fun {{operationId}}Test() {{#reactive}}= runBlockingTest {{/reactive}}{
         {{#allParams}}
-        val {{paramName}}:{{{dataType}}}? = null
+        val {{paramName}}:{{>optionalDataType}} = TODO()
         {{/allParams}}
         val response: ResponseEntity<{{>returnTypes}}> = api.{{operationId}}({{#allParams}}{{paramName}}{{^-last}}, {{/-last}}{{/allParams}})