Telethon: An app does not receive any updates after several hours of work

My app subscribes for updates using self.add_update_handler. It works fine, but after about 5 hours of working it stops receiving updates (according to the web interface there are updates). My log.

DEBUG:root:Handling update for object updates_tg#74ae4240 updates:Vector<Update> users:Vector<User> chats:Vector<Chat> date:date seq:int = Updates
Update was received
DEBUG:root:Handling update for object updates_tg#74ae4240 updates:Vector<Update> users:Vector<User> chats:Vector<Chat> date:date seq:int = Updates
Update was received
DEBUG:root:Handling update for object updates_tg#74ae4240 updates:Vector<Update> users:Vector<User> chats:Vector<Chat> date:date seq:int = Updates
Update was received
INFO:root:Trying to .receive() the request result...
DEBUG:root:Handling container
DEBUG:root:Handling update for object updates_tg#74ae4240 updates:Vector<Update> users:Vector<User> chats:Vector<Chat> date:date seq:int = Updates
Update was received
DEBUG:root:Handling update for object updates_tg#74ae4240 updates:Vector<Update> users:Vector<User> chats:Vector<Chat> date:date seq:int = Updates
Update was received
INFO:root:Trying to .receive() the request result...
DEBUG:root:Handling update for object updates_tg#74ae4240 updates:Vector<Update> users:Vector<User> chats:Vector<Chat> date:date seq:int = Updates
Update was received
INFO:root:Trying to .receive() the request result...
DEBUG:root:Handling update for object updates_tg#74ae4240 updates:Vector<Update> users:Vector<User> chats:Vector<Chat> date:date seq:int = Updates
INFO:root:Trying to .receive() the request result...
DEBUG:root:Handling pong
WARNING:root:Pong confirmed a request
INFO:root:Request result received
DEBUG:root:receive() released the lock
DEBUG:root:Ping sent from the updates thread
DEBUG:root:Trying to receive updates from the updates thread
DEBUG:root:Receiving updates timed out
DEBUG:root:Updates thread released the lock
DEBUG:root:Updates thread acquired the lock
DEBUG:root:send() acquired the lock
DEBUG:root:send() released the lock
DEBUG:root:receive() acquired the lock
INFO:root:Trying to .receive() the request result...
DEBUG:root:Receiving updates timed out
DEBUG:root:Updates thread released the lock