Nextcloud Linux Client does not sync

Good evening

I recently noticed that my Ubuntu Desktop Client from Nextcloud is no longer synchronizing properly. Does anyone know more about this or has anyone had the same experience?
I tried to synchronize manually and also reinstalled the client.

OS: Ubuntu 22.04.4 LTS
Client Version: Nextcloud Desktop Client Version 3.4.2 (Ubuntu)

Can someone help me? What other information do you need?