Grafana - Error while signing in user

Hi all,

I have problems logging in to my grafana installation. I’m running the docker version ( v9.0.0).
When entering username and password the message “Error while signing in user” shows up.

Entering a different password leads to the message “Invalid username or password”, so the entered username and password seems to be correct.

I’ve tried safari and firefox. The issue is the same in both browsers.

Does someone have an idea how to solve this problem?