Webdav service unavailable

Hi everyone,
I installed nextcloud and afterwards tried to connect it by webdav using linux + nautilus.
When i insert the path davs://myhomepage/subfolder/remote.php/dav/files/username
i am asked for user name + pw. Afterwards I get an error ā€œservice unavailableā€.
When I use the client on a windows computer, everything works fine.
I am really confused what the reason might be. Any hints?
Best regards