How to make asterisk and two ip work?

Question

Asterisk

Buenos dias, amigos)
There is an asterisk running cms freepbx with two addresses, public and private from vpn.
There are also clients knocking on public and trunk, standing on the other side of vpn, and behind mikrotik.
The trunk allows the aster to register only if the aster accesses it from the vpn address, so you have to do it
externip=10.223.223.224
.

Contact: <sip:[email protected]хххюх:51392;rinstance=6c6b489612255628>
To: <sip:895151ххххх@185.11.хх.ххх>
From: "500"<sip:[email protected]хх.хх>;tag=019a8473

And the actual result

�\iV��^N^@^Q^B^@^@^Q^B^@^@�q^_�7�^@^L)M,^N^H^@E`^B^C^Ub^@^@@^Q^L_�^KI�^��^E^S���^A���SIP/2.0 403 Forbidden
Via: SIP/2.0/UDP 94.228.хх.ххх51392;branch=z9hG4bK-524287-1---0fe4a30e36ba8328;received=94.228ххх.хх;rport=51392
From: "500"<sip:[email protected]хх.ххх>;tag=891f292d
To: <sip:[email protected]хх.ххх>;tag=as75ba73b1

Why?
TP on the side of the trunk says that the packet comes from the public address, and not from the vpn internal address

Answer 1

did you try to specify the required IP in the trunk config?

Answer 2

It seems to me that you have problems with routing - where will the default route look like?
route-n