mirroring: You are not allowed to force push code to a protected branch on this project

From nowhere, just like #280516 (moved), got a notification of failure and retry is not helping.

Summary

Working mirror (github) started to output an error all of a sudden.

Steps to reproduce

N/A (Pure luck?) Both my cases are github mirrors

What is the current bug behavior?

You are not allowed to force push code to a protected branch on this project. error in Settings -> Repo -> Mirroring

What is the expected correct behavior?

No errors