Connection to Nextcloud Server, Connection Failed

Nextcloud version _ 12.03
Operating system and version :
Apache or nginx version:
PHP version (eg, 5.6): 5.6.30
Is this the first time you’ve seen this error?: No, issue from first usage

Can you reliably replicate it? (If so, please outline steps):
Using the nextcloud client on OSX I try to add account.

The issue you are facing:
When I try to connect my OSX MAC client to my next cloud server I input the address

I get the error:
Failed to connect to the secure server address at blablabla… How do you wish to proceed?

I also get the error "Timeout while trying to connect to Nextcloud at

Also i cannot connect to the http version.
I have lets encrypt installed and working.

I can connect via the web interface, and via IOS.

The output of your Nextcloud log in Admin > Logging:
Trusted domain error. “162...*” tried to access using “” as host.

The output of your config.php file in /path/to/nextcloud (make sure you remove any identifiable information!):

The output of your Apache/nginx/system log in /var/log/____:

Just wondering if you ever got an answer to this problem.

I’m having the very same issue with a MacOS user (OSX 10.11.6, using the Nextcloud MacOS client) unable to connect to our Nextcloud 13.0.1 server. He can connect to that same server via WebDAV (or via the web interface), and others can connect to the server using the Windows client, but he can’t connect via the MacOS client.