Today, 09:46:55 UTC, i stopped receiving any Callbacks from VK API server (screenshot: https://prnt.sc/jPl37Ffb27tF)
VK sends requests to my server properly, but receives an unknown unhand (screenshot: https://prnt.sc/W33q7j6LwN8a)
For last few months I hadn't changes the app code or any settings on the VK API server side. I tried to renew my access token, but that didn't change anything.
What could cause this and how can it be fixed?