diff --git a/modules/openapi-generator/src/main/resources/csharp-netcore/modelOneOf.mustache b/modules/openapi-generator/src/main/resources/csharp-netcore/modelOneOf.mustache
index a7756c16045c..6f5257f71602 100644
--- a/modules/openapi-generator/src/main/resources/csharp-netcore/modelOneOf.mustache
+++ b/modules/openapi-generator/src/main/resources/csharp-netcore/modelOneOf.mustache
@@ -73,7 +73,7 @@
         /// the InvalidClassException will be thrown
         /// </summary>
         /// <returns>An instance of {{dataType}}</returns>
-        public {{{dataType}}} Get{{#lambda.titlecase}}{{baseType}}{{/lambda.titlecase}}{{#isArray}}{{#lambda.titlecase}}{{{dataFormat}}}{{/lambda.titlecase}}{{/isArray}}()
+        public {{{dataType}}} Get{{#lambda.titlecase}}{{baseType}}{{#isArray}}{{{dataFormat}}}{{/isArray}}{{/lambda.titlecase}}()
         {
             return ({{{dataType}}})this.ActualInstance;
         }
diff --git a/samples/client/petstore/csharp-netcore/OpenAPIClient-ConditionalSerialization/src/Org.OpenAPITools/Model/PolymorphicProperty.cs b/samples/client/petstore/csharp-netcore/OpenAPIClient-ConditionalSerialization/src/Org.OpenAPITools/Model/PolymorphicProperty.cs
index 0ce4e18eb2ea..9cbd33ed87b0 100644
--- a/samples/client/petstore/csharp-netcore/OpenAPIClient-ConditionalSerialization/src/Org.OpenAPITools/Model/PolymorphicProperty.cs
+++ b/samples/client/petstore/csharp-netcore/OpenAPIClient-ConditionalSerialization/src/Org.OpenAPITools/Model/PolymorphicProperty.cs
@@ -154,7 +154,7 @@ public Object GetObject()
         /// the InvalidClassException will be thrown
         /// </summary>
         /// <returns>An instance of List&lt;string&gt;</returns>
-        public List<string> GetListString()
+        public List<string> GetListstring()
         {
             return (List<string>)this.ActualInstance;
         }
diff --git a/samples/client/petstore/csharp-netcore/OpenAPIClient-httpclient/src/Org.OpenAPITools/Model/PolymorphicProperty.cs b/samples/client/petstore/csharp-netcore/OpenAPIClient-httpclient/src/Org.OpenAPITools/Model/PolymorphicProperty.cs
index 4e8c938e2e97..9df24a07ead8 100644
--- a/samples/client/petstore/csharp-netcore/OpenAPIClient-httpclient/src/Org.OpenAPITools/Model/PolymorphicProperty.cs
+++ b/samples/client/petstore/csharp-netcore/OpenAPIClient-httpclient/src/Org.OpenAPITools/Model/PolymorphicProperty.cs
@@ -155,7 +155,7 @@ public Object GetObject()
         /// the InvalidClassException will be thrown
         /// </summary>
         /// <returns>An instance of List&lt;string&gt;</returns>
-        public List<string> GetListString()
+        public List<string> GetListstring()
         {
             return (List<string>)this.ActualInstance;
         }
diff --git a/samples/client/petstore/csharp-netcore/OpenAPIClient-net47/src/Org.OpenAPITools/Model/PolymorphicProperty.cs b/samples/client/petstore/csharp-netcore/OpenAPIClient-net47/src/Org.OpenAPITools/Model/PolymorphicProperty.cs
index 0ce4e18eb2ea..9cbd33ed87b0 100644
--- a/samples/client/petstore/csharp-netcore/OpenAPIClient-net47/src/Org.OpenAPITools/Model/PolymorphicProperty.cs
+++ b/samples/client/petstore/csharp-netcore/OpenAPIClient-net47/src/Org.OpenAPITools/Model/PolymorphicProperty.cs
@@ -154,7 +154,7 @@ public Object GetObject()
         /// the InvalidClassException will be thrown
         /// </summary>
         /// <returns>An instance of List&lt;string&gt;</returns>
-        public List<string> GetListString()
+        public List<string> GetListstring()
         {
             return (List<string>)this.ActualInstance;
         }
diff --git a/samples/client/petstore/csharp-netcore/OpenAPIClient-net5.0/src/Org.OpenAPITools/Model/PolymorphicProperty.cs b/samples/client/petstore/csharp-netcore/OpenAPIClient-net5.0/src/Org.OpenAPITools/Model/PolymorphicProperty.cs
index 0ce4e18eb2ea..9cbd33ed87b0 100644
--- a/samples/client/petstore/csharp-netcore/OpenAPIClient-net5.0/src/Org.OpenAPITools/Model/PolymorphicProperty.cs
+++ b/samples/client/petstore/csharp-netcore/OpenAPIClient-net5.0/src/Org.OpenAPITools/Model/PolymorphicProperty.cs
@@ -154,7 +154,7 @@ public Object GetObject()
         /// the InvalidClassException will be thrown
         /// </summary>
         /// <returns>An instance of List&lt;string&gt;</returns>
-        public List<string> GetListString()
+        public List<string> GetListstring()
         {
             return (List<string>)this.ActualInstance;
         }
diff --git a/samples/client/petstore/csharp-netcore/OpenAPIClient/src/Org.OpenAPITools/Model/PolymorphicProperty.cs b/samples/client/petstore/csharp-netcore/OpenAPIClient/src/Org.OpenAPITools/Model/PolymorphicProperty.cs
index 0ce4e18eb2ea..9cbd33ed87b0 100644
--- a/samples/client/petstore/csharp-netcore/OpenAPIClient/src/Org.OpenAPITools/Model/PolymorphicProperty.cs
+++ b/samples/client/petstore/csharp-netcore/OpenAPIClient/src/Org.OpenAPITools/Model/PolymorphicProperty.cs
@@ -154,7 +154,7 @@ public Object GetObject()
         /// the InvalidClassException will be thrown
         /// </summary>
         /// <returns>An instance of List&lt;string&gt;</returns>
-        public List<string> GetListString()
+        public List<string> GetListstring()
         {
             return (List<string>)this.ActualInstance;
         }
diff --git a/samples/client/petstore/csharp-netcore/OpenAPIClientCore/src/Org.OpenAPITools/Model/PolymorphicProperty.cs b/samples/client/petstore/csharp-netcore/OpenAPIClientCore/src/Org.OpenAPITools/Model/PolymorphicProperty.cs
index 0ce4e18eb2ea..9cbd33ed87b0 100644
--- a/samples/client/petstore/csharp-netcore/OpenAPIClientCore/src/Org.OpenAPITools/Model/PolymorphicProperty.cs
+++ b/samples/client/petstore/csharp-netcore/OpenAPIClientCore/src/Org.OpenAPITools/Model/PolymorphicProperty.cs
@@ -154,7 +154,7 @@ public Object GetObject()
         /// the InvalidClassException will be thrown
         /// </summary>
         /// <returns>An instance of List&lt;string&gt;</returns>
-        public List<string> GetListString()
+        public List<string> GetListstring()
         {
             return (List<string>)this.ActualInstance;
         }