we checking the status for the notify push service with service notify_push status I get this:
ERROR [notify_push] src/main.rs:77: Self test failed: Error while communicating with nextcloud instance
After service notify_push restart, the error is gone and everything is fine.
I had a similar problem when I first set up Notify_push. For me it was because the Notify_Push service was started before the database service. You can try adding the following line to the [UNIT] section in the file /etc/systemd/system/notify_push.service.
After=mariadb.service
If you are using another database like PostgreSQL, adjust the line accordingly.