Found some error logs on the prod server.
🤔
🤔
Deleted them unread.
Problems solved.

*gasps*

Had the same once error logs where started like 5 years ago and about 22gb size on a 30gb vps. Nothing worked anymore. After some debuging I found that there ain't no free space. So what to delete first? Hmm maybee some old logs... WTF?!?

Just replace the CRITICAL logger calls with REALLYCRITICAL. Or add a cronjob to delete the logs every 5 seconds. Nobody will know...