diff --git a/clearml/task.py b/clearml/task.py
index c87cb223..9527a444 100644
--- a/clearml/task.py
+++ b/clearml/task.py
@@ -3673,14 +3673,14 @@ class Task(_Task):
             # noinspection PyProtectedMember
             task._arguments.copy_from_dict(flatten_dictionary(config_dict), prefix=name)
 
-        def _refresh_args_dict(task, config_dict):
+        def _refresh_args_dict(task, config_proxy_dict):
             # reread from task including newly added keys
             # noinspection PyProtectedMember
-            a_flat_dict = task._arguments.copy_to_dict(flatten_dictionary(config_dict), prefix=name)
+            a_flat_dict = task._arguments.copy_to_dict(flatten_dictionary(config_proxy_dict), prefix=name)
             # noinspection PyProtectedMember
-            nested_dict = config_dict._to_dict()
-            config_dict.clear()
-            config_dict.update(nested_from_flat_dictionary(nested_dict, a_flat_dict))
+            nested_dict = config_proxy_dict._to_dict()
+            config_proxy_dict.clear()
+            config_proxy_dict._do_update(nested_from_flat_dictionary(nested_dict, a_flat_dict))
 
         def _check_keys(dict_, warning_sent=False):
             if warning_sent:
diff --git a/clearml/utilities/proxy_object.py b/clearml/utilities/proxy_object.py
index 1b0c6ca1..43435879 100644
--- a/clearml/utilities/proxy_object.py
+++ b/clearml/utilities/proxy_object.py
@@ -39,10 +39,14 @@ class ProxyDictPostWrite(dict):
         return a_dict
 
     def update(self, E=None, **F):
+        res = self._do_update(E, **F)
+        self._set_callback()
+        return res
+
+    def _do_update(self, E=None, **F):
         res = super(ProxyDictPostWrite, self).update(
             ProxyDictPostWrite(self._update_obj, self._set_callback, E) if E is not None else
             ProxyDictPostWrite(self._update_obj, self._set_callback, **F))
-        self._set_callback()
         return res