diff --git a/aggregator/forms.py b/aggregator/forms.py
index 91cabc6..159145c 100644
--- a/aggregator/forms.py
+++ b/aggregator/forms.py
@@ -17,14 +17,16 @@ class AggregationSourceForm(ModelForm):
         cleaned_data = super(AggregationSourceForm, self).clean()
         invite_link = cleaned_data.pop('invite_link')
         if invite_link:
-            with get_client() as app:
-                try:
-                    upd = app.join_chat(invite_link)
-                    chat = parse_mtproto_chat(app, upd.chats[0])
-                    cleaned_data['chat_id'] = chat.id
-                    Chat.from_obj(chat, app)
-                except ChannelPrivate:
-                    raise ValidationError('I was banned in this chat')
+            app = get_client()
+            app.start()
+            try:
+                upd = app.join_chat(invite_link)
+            except ChannelPrivate:
+                raise ValidationError('I was banned in this chat')
+            app.stop()
+            chat = parse_mtproto_chat(app, upd.chats[0])
+            cleaned_data['chat_id'] = chat.id
+            Chat.from_obj(chat, app)
         return cleaned_data
 
     class Meta: