Why is my NextCloud not visible from the global network?

Question

Apache HTTP Server

LAMP (Ubuntu 20.10, Apache, PHP8.0, MySQL8.0) is installed on the old computer, NextCloud was installed on it. A domain is attached to this server via NoIP and all my test sites were quite visible from the Internet (ports forwarded - everything is fine with that). In general, the cloud itself was visible from the external network until I started playing with NextCloud Talks and installed a certificate from Let's Enctypt. After that, at home from the phone via Wi-Fi, I see the cloud, but not outside the home network. I already changed the Apache config: <VirtualHost *:80>changed the line to <VirtualHost *:443>, enabled WebDAV, rechecked the ports - nothing