OpenVPN Connection and Cannot resolve host address

Hi,
I try to establish an OpenVPN connection from smartphone to IPFire.
I have set up a service of desec.io under Dienst/Dynamisches DNS/Hinzufügen.
The hostname xxxx.dedyn.io is displayed green. The assigned IP from the provider is
identical to the updated IP at desec.io.

When building an OpenVPN connection with OpenVPN for Android, I get the error:
Cannot resolve host address:
xxxx.dedyn.de:port (No address associated with hostname)

I use
IPFire 2.29 (x86_64) - Core-Update 194 and a smartphone (Android 13)
with OpenVPN for Android 0.7.61 from F-Droid store.

I found this Threat.

I have reconfigured:
Globale Einstellungen,
Erweiterte Server-Optionen,
Zertifizierungsstellen und -schlüssel sowie
Verbindungsstatus und -kontrolle

I then downloaded the xxxx-TO-IPFire.zip file,
copied to the smartphone in the download directory and unpacked 5 files there:
cacert.pem
xxxx.key
xxxx.pem
xxxx-TO-IPFire.ovpn
ta.key

My steps are as in the Threat mentioned above:
1:
On the OpenVPN for Android screen there is an icon of a white box with a downwards pointing arrow… I press this and it opens a file searcher on my android phone. I then navigate to the directory I have stored the config files on and select the .ovpn file, which is the only one highlighted.
So I did it.

The app then goes to the Convert Config File screen and you can accept or change the Profile Name that it suggests.
So I did it.

I then press the tick nark at the top right hand side of the app screen.
So I did it.

I am then on the app page showing all the profiles that have been created. This now contains the one I just created.
Exactly.

I press the profile name I just created …
So I did it.

i get this info:

Cannot resolve host address:
xxxx.dedyn.de:port (No address associated with hostname)

What am I doing wrong.

Thanks for help.

Hi,
I no longer use the service desec.io. Why this does not work as described above, I have not studied further.

Kind regards

Did you check the IP block list and the IPS system logs?
or turn them off and try again?

first xxxx.dedyn.io is green
then you try to connect to xxxx.dedyn.de

this would not work ^^ these are cleary different TLD