Configuration detection - No access to CalDAV or CardDAV services

Hi.
I just installed a new ncp and created a new user “jan”.
Now i try to sync my android but i receive the error:
“Configuration detection - No access to CalDAV or CardDAV services”

I did everything like decribed here:
https://ownyourbits.com/2017/12/30/sync-nextcloud-tasks-calendars-and-contacts-on-your-android-device/

The URL is given by the nextcloud-app, the user is “jan” with his password.

What’s wrong? Do i have to take the given ncp-account?

I rebooted ncp and also tried with thunderbird (lightning) but it does not work.there too.

Strange…

Ok, i configured the portforwarding by myself and wrong.
Didi it by ncp and now it seems to work!