I can’t hear voices in one direction, how to set up sip?

Question

Asterisk

Good afternoon, help in resolving the issue of

Network A 192.168.55.0/24. It has an IP PBX FreePBX 192.168.55.136 (main network)
Network B 192.168.1.0/24. IP phone yealink 192.168.1.72 (branch network) is installed in it

Network A 192.168.55.0/24 - zyxel gateway is installed
Network B 192.168.1.0/24 - zyxel gateway is installed

Both networks are connected via l2tp / ipsec

In network B, the zyxel gateway was replaced with mikrotik hEX S

After the replacement, the voice disappeared when calling from an ip phone from a branch. The call comes from the branch, on the other end they pick up the phone and answer, but the caller is not heard.

What rules on the firewall still need to be added? I believe that voice traffic is being cut somewhere

Answer 1

who is the sip server?