Android client cannot connect to my PMS

Hello, I’m running PMS with Docker on my own server domain. I can access the web interface https://mydomain.com/web.

When accessing from the Android client, it says mydomain.com is currently unavailable, which is not true.

How to make the Android client access the PMS running on the internet?

Note: the PMS is exposing only ports 80 and 443.

Duplicate of How does Plex evaluates if a server is online?
closing.