diff --git a/experimental/lambda/src/main/java/io/serverlessworkflow/impl/executors/func/AbstractJavaCallExecutor.java b/experimental/lambda/src/main/java/io/serverlessworkflow/impl/executors/func/AbstractJavaCallExecutor.java
index 99e464d72..fe890139c 100644
--- a/experimental/lambda/src/main/java/io/serverlessworkflow/impl/executors/func/AbstractJavaCallExecutor.java
+++ b/experimental/lambda/src/main/java/io/serverlessworkflow/impl/executors/func/AbstractJavaCallExecutor.java
@@ -38,10 +38,11 @@ protected AbstractJavaCallExecutor(Optional<Class<T>> inputClass) {
   @Override
   public CompletableFuture<WorkflowModel> apply(
       WorkflowContext workflowContext, TaskContext taskContext, WorkflowModel input) {
-    Object result = callJavaFunction(workflowContext, taskContext, model2Input(input));
+    Object result =
+        convertResponse(callJavaFunction(workflowContext, taskContext, model2Input(input)));
     WorkflowModelFactory modelFactory = workflowContext.definition().application().modelFactory();
     return result instanceof CompletableFuture future
-        ? future.thenApply(v -> output2Model(modelFactory, input, v))
+        ? future.thenApply(v -> output2Model(modelFactory, input, convertResponse(v)))
         : CompletableFuture.completedFuture(output2Model(modelFactory, input, result));
   }
 
@@ -60,6 +61,6 @@ protected Object convertResponse(Object obj) {
 
   protected WorkflowModel output2Model(
       WorkflowModelFactory modelFactory, WorkflowModel input, Object result) {
-    return modelFactory.fromAny(input, convertResponse(result));
+    return modelFactory.fromAny(input, result);
   }
 }