My NC Mobile app gives a warning that the server is in maintenance mode

a few days ago I installed nextcloud with a premade os called Nextcloud pi (btw its installed on a rpi4b with 8gb ram), the os is based on Raspberry Pi OS/Debian 11 and it has nextcloud preinstalled. When I tried to connect my phone to the server it worked but there was a message which says that the server is in maintenance mode, but its not (I checked the corosponding file)
Has anyone experienced the same problem? If yes how did you solve the problem?