diff --git a/modules/openapi-generator/src/main/resources/kotlin-client/data_class.mustache b/modules/openapi-generator/src/main/resources/kotlin-client/data_class.mustache
index 1cc3e8d299c0..d97d9fa54366 100644
--- a/modules/openapi-generator/src/main/resources/kotlin-client/data_class.mustache
+++ b/modules/openapi-generator/src/main/resources/kotlin-client/data_class.mustache
@@ -292,6 +292,7 @@ import {{packageName}}.infrastructure.ITransformForStorage
             }
             {{/required}}
             {{#items.isPrimitiveType}}
+            {{^items.isArray}}
             // ensure the items in json array are primitive
             if (jsonObj["{{#lambda.escapeDollar}}{{baseName}}{{/lambda.escapeDollar}}"] != null) {
               for (i in 0 until jsonObj.getAsJsonArray("{{#lambda.escapeDollar}}{{baseName}}{{/lambda.escapeDollar}}").size()) {
@@ -300,6 +301,7 @@ import {{packageName}}.infrastructure.ITransformForStorage
                 }
               }
             }
+            {{/items.isArray}}
             {{/items.isPrimitiveType}}
             {{/items.isModel}}
             {{/isArray}}