Incoming Webhook bot loses some channels connections

Hi colleagues,

We have been using Incoming Webhook for months. Since 12/17 we noticed that some channel connections become invalid: webhook request returns status code 400 and error "No channel or user can be found with the given to_jid". I "regenerate" token, it helps, but after hours it could happen again. Or continue working. Or stop working again with the same error later.

Did anyone face the same problem? What is the reason? How to resolve it? We didn't changed anything using webhook on our side. I couldn't be sure that i'll not miss some important notification, but always regenerate token is just a temporary solution, it makes me really wistful