[SR-Users] Re: Change the To Header in the failure_route

To ensure the reply in failure_route[ID] uses the correct "to tag" from previous SIP messages, you need to manually add the "to tag" parameter from the 180 Ringing or other related responses. Since uac_replace_to() doesn't work in failure_route, you can use the $ct variable to access and modify the "To" header. Here's an example: failure_route[ID] { # Extract the to-tag from the previous response (e.g., 180 Ringing) $avp(to_tag) = $(ct{uri.param,tag}); # Process and send a reply with the extracted to-tag append_to_reply("To: $ct{uri.param.tag}\r\n"); t_send_reply(486, "Busy Here"); } Make sure you adjust the script according to your specific requirements and the context of your SIP message handling.