Why does not hang up in asterisk?

Question

Asterisk

Good day. Installed Asterisk 18 on Centos 8 PBX and phones behind different nats. Ports are forwarded, phones are registered, I talk without problems. If you change the port in sip.conf from default to any other (I also correct forwarding on Mikrotik), miracles begin. Phones are still registered and calls go normally, but after I hang up from a device that is not in the same network with the PBX, the clear signal does not go through and the channel remains up. Error 481 call leg transaction does not exist arrives. Any ideas where to dig?

Answer 1

The solution turned out to be simple. When forwarding the service port (5060 by default), do not forget to specify the port 1 more in the forwarding (it is also needed). I hope it will be useful to someone else)