How to set up incoming sip calls?

Question

SIP

Good evening. At work, they provided ip PBX agate ux-3710 for use. We took a sip-trunk from a local provider of a city connection.
The guys who provided the ats-ku tried to set it up, but it only turned out to set up incoming calls.
When you try to dial a number from the phone's ip, it almost instantly says on the device screen that the number is not available.
The provider that provides sip-trunk says that on our part we need to disable authorization for outgoing calls. At the same time, atsky adjusters say that we have it disabled.
The connection diagram of the PBX itself is as follows.
On the Internet from the provider there is a Mikrotik cable from it goes to the crypto gateway, and the PBX is already connected to the crypto gateway itself.
Phones are also connected, you can say behind the crypto-gateway.
In the router, the required port is forwarded to the address of the PBX behind the crypto gateway. The service in Mikrotik that is advised to disable SIP-ALG is disabled.
What else could be the reason? I just want to sort this out for myself.

Answer 1

You mean there are no beeps? Maybe the dialing plan in the PBX is not correct? Crypto gateway - what is it ??? (I just hear the name for the first time)
If you connect the PBX directly to Mikrotik, does it work?

Answer 2

The service in Mikrotik that is advised to disable SIP-ALG is disabled.

Let's start by turning it on.
In general, in such a description "from a blonde" it is somewhat difficult to isolate the necessary information - telepathic abilities are overloaded.

Answer 3

Capture and share a PCAP call dump.