We had migrated all the DID's to SIP provider, however the Toll free numbers we had from Different Provider. All agents phone masked with TFN, But Since TFN from different provider SIP ITSP rejected the outbound calls agent make. To pass the TFN we need to add a Diversion header so that it will be authenticated from ITST and then call will be routed
request INVITE sip-header From modify "(.*sip:Your TFN @.*)" "\1\x0D\x0ADiversion: <sip:DID from ITSP@CUEB IP Address>"
Below Diversion header also work
request INVITE sip-header Diversion add "Diversion: <sip:DID@CUEB IP Address>"
