I have now removed Mobilizon, then repeated all the steps of postgres migration .
After that the restart still had no success, I think it has something to do with the PID file.
Aug 23 09:54:51 systemd[1]: postgresql@13-main.service: Can't open PID file /run/postgresql/13-main.pid (yet?) after start: Operation not permitted
After I restarted the server completely, the postgres seems to run correctly now.
However, now wiki.js does not work anymore. I skipped the migration in the yunohost-admin. Are there any other steps that need to be taken?