diff --git a/Packages/com.github.homuler.mediapipe/Runtime/Scripts/Unity/OutputStream.cs b/Packages/com.github.homuler.mediapipe/Runtime/Scripts/Unity/OutputStream.cs
index a984fb296..ebf90ebdd 100644
--- a/Packages/com.github.homuler.mediapipe/Runtime/Scripts/Unity/OutputStream.cs
+++ b/Packages/com.github.homuler.mediapipe/Runtime/Scripts/Unity/OutputStream.cs
@@ -389,7 +389,7 @@ protected static Status.StatusArgs InvokeIfOutputStreamFound(IntPtr graphPtr, in
         var isFound = _InstanceTable.TryGetValue(streamId, out var outputStream);
         if (!isFound)
         {
-          return Status.StatusArgs.NotFound($"OutputStream with id {streamId} is not found");
+          return Status.StatusArgs.NotFound($"OutputStream with id {streamId} is not found, maybe already GCed");
         }
         if (outputStream.calculatorGraph.mpPtr != graphPtr)
         {