Hi David, the second example looks correct: From: "14254350027" <sip:14254350027@1.1.18.171<mailto:sip%3A14254350027@1.1.18.171>>;tag=13133439191609 the first one not (no brackets, wrong order of display name and uri. From: sip:14254350027@1.1.18.171<mailto:sip%3A14254350027@1.1.18.171>"14254350027" <>;tag=13133439191609 Do you see this for all test calls? If yes, consider to open an issue on our github tracker about it. Cheers, Henning -- Henning Westerholt – https://skalatan.de/blog/ Kamailio services – https://gilawa.com<https://gilawa.com/> From: sr-dev &lt;sr-dev-bounces(a)lists.kamailio.org&gt; On Behalf Of David Escartin Sent: Tuesday, March 3, 2020 6:10 PM To: Kamailio (SER) - Development Mailing List &lt;sr-dev(a)lists.kamailio.org&gt; Subject: [sr-dev] uac_replace_from rare behaviour Hello all we just noticed an issue using this function when we call it with 2 params (display and uri) and the SIP INVITE comes with a From uri like sip:anonymous@anonymous.invalid; tag=13133439191609, without <> delimiters, then doing the uac replace in the ACK we have 2(14923) DEBUG: uac [replace.c:922]: replace_callback(): DOWNSTREAM direction detected - replacing uri with the new uri 2(14923) DEBUG: uac [replace.c:943]: replace_callback(): Replace [ sip:anonymous@anonymous.invalid] with ["14254350027" sip:14254350027@1.1.18.171<mailto:sip%3A14254350027@1.1.18.171>] 2(14923) DEBUG: uac [replace.c:980]: replace_callback(): inserting display ["14254350027"] And this is the From header replaced From: sip:14254350027@1.1.18.171<mailto:sip%3A14254350027@1.1.18.171>"14254350027" <>;tag=13133439191609 But if the call comes with a From header like <sip:anonymous@anonymous.invalid>; tag=13133439191609 Then this is the From header replaced 2(19741) DEBUG: uac [replace.c:922]: replace_callback(): DOWNSTREAM direction detected - replacing uri with the new uri 2(19741) DEBUG: uac [replace.c:943]: replace_callback(): Replace [ sip:1241342@1.1.18.171:5074<http://sip:1241342@1.1.18.171:5074>] with ["14254350027" sip:14254350027@1.1.18.171<mailto:sip%3A14254350027@1.1.18.171>] 2(19741) DEBUG: uac [replace.c:980]: replace_callback(): inserting display ["14254350027"] From: "14254350027" <sip:14254350027@1.1.18.171<mailto:sip%3A14254350027@1.1.18.171>>;tag=13133439191609 Were you aware of this kind of behaviour? If possible we will look for a patch for this. thanks a lot and regards david