Can't install Nextcloud

[Axiq]

Hello.
I can't install the plugin Nextcloud on TrueNAS Core (TrueNAS-12.0-U8). The installation is aborted with an error:

Error: j.nextcloud had a failure Exception: RuntimeError Message: Last 10 lines: + + + + + writing new private key to '/usr/local/etc/letsencrypt/live/truenas/server.key' ----- Signature ok subject=O = TrueNAS (Nextcloud), CN = localhost Getting CA Private Key mysqladmin: connect to server at 'localhost' failed error: 'Can't connect to local MySQL server through socket '/tmp/mysql.sock' (2)' Check that mysqld is running and that the socket: '/tmp/mysql.sock' exists! Partial plugin destroyed

What can be done?
Thanks.