diff --git a/clearml_agent/backend_api/session/session.py b/clearml_agent/backend_api/session/session.py
index 407b3ba..dafa4c7 100644
--- a/clearml_agent/backend_api/session/session.py
+++ b/clearml_agent/backend_api/session/session.py
@@ -114,7 +114,7 @@ class Session(TokenManager):
 
         if ENV_API_DEFAULT_REQ_METHOD.get(default=None):
             # Make sure we update the config object, so we pass it into the new containers when we map them
-            self.config["api.http.default_method"] = ENV_API_DEFAULT_REQ_METHOD.get()
+            self.config.put("api.http.default_method", ENV_API_DEFAULT_REQ_METHOD.get())
             # notice the default setting of Request.def_method are already set by the OS environment
         elif self.config.get("api.http.default_method", None):
             def_method = str(self.config.get("api.http.default_method", None)).strip()
diff --git a/clearml_agent/backend_config/config.py b/clearml_agent/backend_config/config.py
index 8401d36..a1f03f7 100644
--- a/clearml_agent/backend_config/config.py
+++ b/clearml_agent/backend_config/config.py
@@ -294,6 +294,9 @@ class Config(object):
             )
         return value
 
+    def put(self, key, value):
+        self._config.put(key, value)
+
     def to_dict(self):
         return self._config.as_plain_ordered_dict()