The group stopped receiving notifications of new messages (Callback API), other events work. What to do?

Question

API

I have a bot in VK (for conversations). Everything worked great before. But yesterday notifications about actions (requests) stopped coming, namely message_new
. Other requests, such as confirmation and others, work and come normally.
Didn't touch anything and didn't touch me. Everything worked great before. The bot just stopped detecting new messages for some reason.
What can be wrong? VK tech support has been silent for 3 days

Answer 1

1. If confirmation arrives, check in the settings in the group whether the callback server is confirmed
2. Check if this checkbox is checked in the server settings
3. Try to update the community access key (access_token)
The server should respond to requests with "ok" if for some reason they do not are sent to him, he can suspend the sending of events in the group.