How to access Tiny Server from an external IP?

Question

network hardware

Can't login to Tiny Server using external_ip:80 . It redirects to the router configuration, just as if it were accessing 192.168.88.1.
IP is static, port is standard 80.
I did forwarding, I changed the port (1337, 4444 and generally random). By the checkers "Port is open", but I can't get to the "Tiny Server Installation Successful" check page.
I created rules in the firewall for the port, turned off the firewall.
Through localhost and internal_ip_machine: 80 everything works. From the phone I go through the internal_ip_machine: 80 , everything is also ok.
Router Mikrotik hAP ac lite.
Maybe I'm doing something fundamentally wrong and this garbage should not work at all. :D
I watched guides on this topic, everything is simple and smooth there - set it up, went in, SUCCESS.

Answer 1

Because the port is occupied by the web interface of the router. Make HTTP port 8080 on the server and forward it outside. Knock on ip:8080 too.

Answer 2

Hairpin NAT will save you