Changed trusted domains in config file , still "access through untrusted domain..." | Synology DS415+


I successfully installed Nextcloud on my Synology Diskstation. Now I want to be able to access the Synology from outside my network. I changed the config file and added my domain to trusted domains but I’m still getting that “Access through untrusted domain etc” when I try to connect via my domain from outside the network. I was under the impression that after changing the config it should work? Do I have to do additional steps to make it work?

Thanks in advance