diff --git a/plugins/flutter/CHANGELOG.md b/plugins/flutter/CHANGELOG.md
index 4687af75..183d54fd 100644
--- a/plugins/flutter/CHANGELOG.md
+++ b/plugins/flutter/CHANGELOG.md
@@ -25,6 +25,6 @@ The initial version. Hello, world!
 + Add `math.isnan` and `math.isinf`
 + Fix a bug of `__checkType`
 
-## 0.5.0+2
+## 0.5.0+3
 
 + Fix a bug on Windows
\ No newline at end of file
diff --git a/plugins/flutter/lib/pocketpy.dart b/plugins/flutter/lib/pocketpy.dart
index b364d425..31375942 100644
--- a/plugins/flutter/lib/pocketpy.dart
+++ b/plugins/flutter/lib/pocketpy.dart
@@ -101,7 +101,7 @@ class VM {
     var ret = _Bindings.pkpy_vm_eval(pointer, _Str(source).p);
     if (ret == ffi.nullptr) return null;
     String s = ret.toDartString();
-    calloc.free(ret);
+    _Bindings.pkpy_delete(ret);
     return s;
   }
 
@@ -118,7 +118,7 @@ class VM {
     var ret = _Bindings.pkpy_vm_get_global(pointer, _Str(name).p);
     if (ret == ffi.nullptr) return null;
     String s = ret.toDartString();
-    calloc.free(ret);
+    _Bindings.pkpy_delete(ret);
     return s;
   }
 
@@ -142,7 +142,7 @@ class ThreadedVM extends VM {
     var ret = _Bindings.pkpy_tvm_read_jsonrpc_request(pointer);
     if (ret == ffi.nullptr) return null;
     String s = ret.toDartString();
-    calloc.free(ret);
+    _Bindings.pkpy_delete(ret);
     return s;
   }
 
diff --git a/plugins/flutter/pubspec.yaml b/plugins/flutter/pubspec.yaml
index 45458116..9b0faaf1 100644
--- a/plugins/flutter/pubspec.yaml
+++ b/plugins/flutter/pubspec.yaml
@@ -1,6 +1,6 @@
 name: pocketpy
 description: A lightweight Python interpreter for game engines.
-version: 0.5.0+2
+version: 0.5.0+3
 homepage: https://pocketpy.dev
 repository: https://github.com/blueloveth/pocketpy