[9.0.1] open_basedir restriction in Filesystem.php

I moved a site to a new Server. I had an issue with sessions but i fixed it with sessions in database. The site worked but …

now I get this error:

file_exists(): open_basedir restriction in effect. File(/httpdocs/updates/concrete-cms-9.0.1/concrete/routes/panels.php) is not within the allowed path(s): (/var/www/vhosts/hostingXXXXXX.netcup.net/:/tmp/)

in
Filesystem.php:

     public function exists($path)
        {
            return file_exists($path);
        }

How can i tell Concrete that “/httpdocs/…” is a sub directory of “/var/www/vhosts/hostingXXXXXX.netcup.net/”?

You probably need to empty the cache folder you have in application/files