Trunk is not answer

Hi,
Again with other trunk. My test trunk is working like a harm… but production one unfortunately is not answer. It is trying request in the loop OPTIONS/REGISTER, but without success.
When I try to connect trunk using MicroSIP it is working:
`23:01:44.983 pjsua_core.c …TX 726 bytes Request msg REGISTER/cseq=39190 (tdta05947DFC) to UDP 212.xxx.xxx.xx3:5060:
REGISTER sip:212.xxx.xxx.xx3 SIP/2.0
Via: SIP/2.0/UDP 212.xxx.xxx.xx6:52456;rport;branch=z9hG4bKPj2dbc29de63014aa5a009c8b40e754140
Route: sip:212.xxx.xxx.xx3;lr
Max-Forwards: 70
From: sip:[email protected];tag=6dc79c0bcbbd43e5be8839f4c949fc58
To: sip:[email protected]
Call-ID: 26be4c77bccd4c50938c458f73ee5539
CSeq: 39190 REGISTER
User-Agent: MicroSIP/3.21.6
Contact: sip:[email protected]:52456;ob
Expires: 300
Allow: PRACK, INVITE, ACK, BYE, CANCEL, UPDATE, INFO, SUBSCRIBE, NOTIFY, REFER, MESSAGE, OPTIONS
Authorization: Digest username=“telemorele”, realm=“aloalo”, nonce=“7d10ace0”, uri=“sip:212.xxx.xxx.xx3”, response=“ff805542567b177ae531d673363ed236”
Content-Length: 0

–end msg–
23:01:44.983 tsx05912F4C …State changed from Null to Calling, event=TX_MSG
23:01:44.984 sip_endpoint.c Processing incoming message: Response msg 100/REGISTER/cseq=39190 (rdata09A96094)
23:01:44.985 pjsua_core.c .RX 460 bytes Response msg 100/REGISTER/cseq=39190 (rdata09A96094) from UDP 212.xxx.xxx.xx3:5060:
SIP/2.0 100 Trying
Via: SIP/2.0/UDP 212.xxx.xxx.xx6:52456;rport;branch=z9hG4bKPj2dbc29de63014aa5a009c8b40e754140;received=212.xxx.xxx.xx6
From: sip:[email protected];tag=6dc79c0bcbbd43e5be8839f4c949fc58
To: sip:[email protected]
Call-ID: 26be4c77bccd4c50938c458f73ee5539
CSeq: 39190 REGISTER
User-Agent: adescom CTM5000
Allow: INVITE, ACK, CANCEL, OPTIONS, BYE, REFER, SUBSCRIBE, NOTIFY, INFO
Max-Forwards: 70
Content-Length: 0

–end msg–
23:01:44.985 tsx05912F4C .Incoming Response msg 100/REGISTER/cseq=39190 (rdata09A96094) in state Calling
23:01:44.985 tsx05912F4C ..State changed from Calling to Proceeding, event=RX_MSG
23:01:44.985 sip_endpoint.c Processing incoming message: Request msg OPTIONS/cseq=102 (rdata09A9308C)
23:01:44.985 pjsua_core.c .RX 522 bytes Request msg OPTIONS/cseq=102 (rdata09A9308C) from UDP 212.xxx.xxx.xx3:5060:
OPTIONS sip:[email protected]:52456;ob SIP/2.0
Via: SIP/2.0/UDP 212.xxx.xxx.xx3:5060;branch=z9hG4bK2caa2ad8;rport
From: “aloalo” sip:[email protected];tag=as2700bc90
To: sip:[email protected]:52456;ob
Contact: sip:[email protected]
Call-ID: 633a204d4da262db7acdd2847347b9ae3297656140
CSeq: 102 OPTIONS
User-Agent: adescom CTM5000
Max-Forwards: 70
Date: Mon, 14 Apr 2025 21:01:42 GMT
Allow: INVITE, ACK, CANCEL, OPTIONS, BYE, REFER, SUBSCRIBE, NOTIFY, INFO
Content-Length: 0

–end msg–
23:01:44.985 endpoint .Response msg 200/OPTIONS/cseq=102 (tdta05944DE4) created
23:01:44.985 pjsua_core.c .TX 743 bytes Response msg 200/OPTIONS/cseq=102 (tdta05944DE4) to UDP 212.xxx.xxx.xx3:5060:
SIP/2.0 200 OK
Via: SIP/2.0/UDP 212.xxx.xxx.xx3:5060;rport=5060;received=212.xxx.xxx.xx3;branch=z9hG4bK2caa2ad8
Call-ID: 633a204d4da262db7acdd2847347b9ae3297656140
From: “aloalo” sip:[email protected];tag=as2700bc90
To: sip:[email protected];ob;tag=z9hG4bK2caa2ad8
CSeq: 102 OPTIONS
Allow: PRACK, INVITE, ACK, BYE, CANCEL, UPDATE, INFO, SUBSCRIBE, NOTIFY, REFER, MESSAGE, OPTIONS
Accept: application/sdp, application/pidf+xml, application/xpidf+xml, application/simple-message-summary, message/sipfrag;version=2.0, application/im-iscomposing+xml, text/plain
Supported: replaces, 100rel, timer, norefersub, trickle-ice
Allow-Events: presence, message-summary, refer
User-Agent: MicroSIP/3.21.6
Content-Length: 0`

But using FreePBX unfortunately not. Tried with many options with Proxy/without.
I have two network interfaces but routing is working. I have no idea…

`<— Transmitting SIP request (460 bytes) to UDP:212.xxx.xxx.xx3:5060 —>
OPTIONS sip:[email protected]:5060 SIP/2.0
Via: SIP/2.0/UDP 212.xxx.xxx.xx6:5060;rport;branch=z9hG4bKPj599f84bf-de47-4bb8-beef-f81bc68b8d39
From: sip:[email protected];tag=f32a2adb-e5ee-405a-832e-9fff3b49c1b0
To: sip:[email protected]
Contact: sip:[email protected]:5060
Call-ID: 23d012fa-7cb2-4128-9ba8-9ea50d5bacaa
CSeq: 10385 OPTIONS
Max-Forwards: 70
User-Agent: FPBX-17.0.19.24(22.1.0)
Content-Length: 0

<— Transmitting SIP request (596 bytes) to UDP:212.xxx.xxx.xx3:5060 —>
REGISTER sip:212.xxx.xxx.xx3:5060 SIP/2.0
Via: SIP/2.0/UDP 212.xxx.xxx.xx6:5060;rport;branch=z9hG4bKPjc876101f-a9a1-4846-8df7-14c027f35b08
From: sip:[email protected];tag=b30218bf-7306-4a7a-938e-ac4a11e253b7
To: sip:[email protected]
Call-ID: 13c56a51-6390-41ad-aa1d-120663ec0126
CSeq: 25587 REGISTER
Contact: sip:[email protected]:5060;line=kvafznh
Expires: 3600
Allow: OPTIONS, INVITE, ACK, BYE, CANCEL, UPDATE, PRACK, REGISTER, SUBSCRIBE, NOTIFY, PUBLISH, INFO, MESSAGE, REFER
Max-Forwards: 70
User-Agent: FPBX-17.0.19.24(22.1.0)
Content-Length: 0

<— Transmitting SIP request (460 bytes) to UDP:212.xxx.xxx.xx3:5060 —>
OPTIONS sip:[email protected]:5060 SIP/2.0
Via: SIP/2.0/UDP 212.xxx.xxx.xx6:5060;rport;branch=z9hG4bKPj599f84bf-de47-4bb8-beef-f81bc68b8d39
From: sip:[email protected];tag=f32a2adb-e5ee-405a-832e-9fff3b49c1b0
To: sip:[email protected]
Contact: sip:[email protected]:5060
Call-ID: 23d012fa-7cb2-4128-9ba8-9ea50d5bacaa
CSeq: 10385 OPTIONS
Max-Forwards: 70
User-Agent: FPBX-17.0.19.24(22.1.0)
Content-Length: 0

<— Transmitting SIP request (596 bytes) to UDP:212.xxx.xxx.xx3:5060 —>
REGISTER sip:212.xxx.xxx.xx3:5060 SIP/2.0
Via: SIP/2.0/UDP 212.xxx.xxx.xx6:5060;rport;branch=z9hG4bKPjc876101f-a9a1-4846-8df7-14c027f35b08
From: sip:[email protected];tag=b30218bf-7306-4a7a-938e-ac4a11e253b7
To: sip:[email protected]
Call-ID: 13c56a51-6390-41ad-aa1d-120663ec0126
CSeq: 25587 REGISTER
Contact: sip:[email protected]:5060;line=kvafznh
Expires: 3600
Allow: OPTIONS, INVITE, ACK, BYE, CANCEL, UPDATE, PRACK, REGISTER, SUBSCRIBE, NOTIFY, PUBLISH, INFO, MESSAGE, REFER
Max-Forwards: 70
User-Agent: FPBX-17.0.19.24(22.1.0)
Content-Length: 0

<— Transmitting SIP request (460 bytes) to UDP:212.xxx.xxx.xx3:5060 —>
OPTIONS sip:[email protected]:5060 SIP/2.0
Via: SIP/2.0/UDP 212.xxx.xxx.xx6:5060;rport;branch=z9hG4bKPj599f84bf-de47-4bb8-beef-f81bc68b8d39
From: sip:[email protected];tag=f32a2adb-e5ee-405a-832e-9fff3b49c1b0
To: sip:[email protected]
Contact: sip:[email protected]:5060
Call-ID: 23d012fa-7cb2-4128-9ba8-9ea50d5bacaa
CSeq: 10385 OPTIONS
Max-Forwards: 70
User-Agent: FPBX-17.0.19.24(22.1.0)
Content-Length: 0

<— Transmitting SIP request (596 bytes) to UDP:212.xxx.xxx.xx3:5060 —>
REGISTER sip:212.xxx.xxx.xx3:5060 SIP/2.0
Via: SIP/2.0/UDP 212.xxx.xxx.xx6:5060;rport;branch=z9hG4bKPjc876101f-a9a1-4846-8df7-14c027f35b08
From: sip:[email protected];tag=b30218bf-7306-4a7a-938e-ac4a11e253b7
To: sip:[email protected]
Call-ID: 13c56a51-6390-41ad-aa1d-120663ec0126
CSeq: 25587 REGISTER
Contact: sip:[email protected]:5060;line=kvafznh
Expires: 3600
Allow: OPTIONS, INVITE, ACK, BYE, CANCEL, UPDATE, PRACK, REGISTER, SUBSCRIBE, NOTIFY, PUBLISH, INFO, MESSAGE, REFER
Max-Forwards: 70
User-Agent: FPBX-17.0.19.24(22.1.0)
Content-Length: 0
`

I will be grateful for any help.
Krzysztof

You are getting no replies from the far end, but are either not behind NAT, or have reasonable public address and local network settings.

You need to trace the request, and if it reaches its destination, the corresponding response, through the network, and find out where the chain breaks.