Hi ppl, If I add a FQDN advertise address to the listen statement, *is_first_hop() <https://kamailio.org/docs/modules/4.3.x/modules/siputils.html#siputils.f.is_first_hop>* seems to return FALSE no matter how I play with the listen and alias settings. listen=udp:1.1.1.1:5060 advertise sip.mydomain.net:5060 alias="sip.mydomain.net:5060" This statement doesn't get executed in the *onreply_route* *onreply_route[MANAGE_REPLY] {* *if(is_first_hop())* *set_contact_alias(); # contact alias doesn't get set?* *}* *is_first_hop()* *"The function returns true if the proxy is first hop after the original sender. For incoming SIP replies, it means that top Record-Route URI is 'myself' and source address is not matching it"* *This is the reply.* 2018/10/03 17:03:38.276846 2.2.2.2:62033 -> 1.1.1.1:5060 SIP/2.0 200 OK Via: SIP/2.0/UDP sip.mydomain.net:5060 ;branch=z9hG4bK49b3.bfbe15.0;received=1.1.1.1 Via: SIP/2.0/UDP 10.10.10.10:5060;rport=5060;branch=z9hG4bK1af96136 *Record-Route*: <sip:sip.mydomain.net;lr=on;did=4cc.734> Contact: <sip:888@10.17.0.35:62033> Suggestions? Thanks.