Nextcloud not reachable using dyndns

Hey guys,
I’m trying to get NC running on a dedicated computer behind a “Fritzbox”.
The ports 22, 80 and 443 are being forwarded.
NC is running fine when using the ip of this computer, nevertheless I preferred using xyz.dyndnss.net since the ip is changing from time to time and I don’t want to whitelist another ip each and every day.
That’s the point where I need your support.
When trying to access NC via ip or ip/nextcloud I get the nc login page.
When trying to access NC via xyz.dyndnss.net I just get a empty page and it keep loading forever or an error message, that this page would be redirecting forever. (Depending on my Apache VHost setup).
For now, I do not care about https. That’s the next step. First I would like to get started using dyndnss.
Please feel free to ask for all the information which you might still need.
Thats my vHost file

<VirtualHost *:80>
ServerName xyz.dyndnss.net
DocumentRoot /var/www/html/nextcloud

<Directory /nextcloud>
Options Indexes FollowSymLinks MultiViews
AllowOverride All
Order allow,deny
Allow from all
Satisfy Any

<Directory /var/www/html/nextcloud/>
Options +FollowSymlinks
AllowOverride All

You are missing a lot of required configuration in your vHost file? Is this your default host or do you have another configuration file for accessing it via IP?

Hi admorgen, thanks for your reply.
I have no additional vHost file in generall.
(I also tested with the enabled default-ssl site but that one is only listening to 443, so shouldn’t change anything)
Could you please tell me which parts I am missing?
Otherwise, a Link to a working vHost file would be really helpfull.
Thanks in advance @admorgan