Hello, if you track the call with the dialog module and then also use the dialog mode in the uac module no variables are stored in the SIP messages. The module will store the information in dialog variables. If you use a persistent dialog DB mode, it will be also saved in the DB and should even be restored at a restart. I remember doing some tests some years ago for a project, and also did some fixes/extensions in this matter. Maybe just give it a try. Cheers, Henning -- Henning Westerholt – https://skalatan.de/blog/ Kamailio services – https://gilawa.com<https://gilawa.com/> From: Duarte Rocha &lt;duarterocha91(a)gmail.com&gt; Sent: Donnerstag, 7. September 2023 19:10 To: sr-users(a)lists.kamailio.org Subject: [SR-Users] Re: uac_replace_to() without RR params I made some more testing and found that calling dlg_manage() before uac_replace() and setting restore_dlg param with value “1” solves my issue and doesn’t add params to Record-Route. In the event of a restart to Kamailio i would like to keep the state of the call and not lose the values on the dialog vars where original To and From headers are stored. In order to do that i thought of saving the original values on a data structure and assigning its value to the lost dialog vars. In order to that i need to be able to access those dialog variables. Is that possible? What is their name? Cheers