WebDAV folder is empty

Hi

I’m an utter noob when it comes to kodi etc. but maybe you can help me.
I’ve installed kodi 16.1 on my pi and wanted to add my library which is on my NAS. My NAS is not in my appartement so i have to access it via internet.
I tried to add it with WebDAV because that was the suggested way after asking google. The thing is, i can’t get to my movies.
I add the dynamic dns name and the port into the mask. Now when I leace the remote path empty it seems to be able to connect but the folder stays empty when I click it. As soon as I add the remote path it won’t even connect to the server anymore. Have I done something wrong?Huh