Nextcloud 28 Docker containers kills itself after a while 503

So I have to say this has happened for a week I guess. Maybe since Nextcloud 28.0.1. But I guess it’s not the reason. The container runs well for 3 hours and then suddenly turns into 503 and the maintenance mode is enabled. If I disable it then again everything works again. But if I do not disable the maintenance mode Nextcloud kills my whole server. Don’t ask me what happens and how it is possible but it happens.

Every container starts the become unhealthy somehow and the CPU usage will go to 100% permanently and the system is unresponsive. How is this Docker container even able to do this? I have limited RAM to 6GB (of 64) and CPU to 2 but this didn’t help either. I’m running everything on unRAID Linux with a i5-13500 so it’s not my system’s fault.

Every time the same procedure. I start it, it runs fine for some hours and then suddenly 503 in the logs and the cloud is in maintenance mode. If I don’t disable it fast enough my system gets killed.

Logs:

172.19.0.76 -  05/Feb/2024:19:39:35 +0100 "GET /ocs/v2.php" 200
172.19.0.76 -  05/Feb/2024:19:39:35 +0100 "GET /ocs/v2.php" 200
172.19.0.76 - xyz 05/Feb/2024:19:39:44 +0100 "GET /ocs/v2.php" 200
172.19.0.76 - xyz 05/Feb/2024:19:39:44 +0100 "GET /ocs/v2.php" 200
172.19.0.76 - xyz 05/Feb/2024:19:39:44 +0100 "PROPFIND /remote.php" 207
crond: USER www-data pid 1688 cmd php -f /var/www/html/cron.php
172.19.0.76 -  05/Feb/2024:19:40:13 +0100 "GET /ocs/v2.php" 503
172.19.0.76 - xyz 05/Feb/2024:19:40:14 +0100 "PROPFIND /remote.php" 503
172.19.0.76 - xyz 05/Feb/2024:19:40:28 +0100 "PROPFIND /remote.php" 503
172.19.0.76 - xyz 05/Feb/2024:19:40:28 +0100 "GET /index.php" 503

Anybody with an idea or the same experience?