I am using Twilio as SIP trunk on freepbx and when I try to call forward on external number from my pbx extension to external number, Twilio reject that call forwarding and reply that I need to use REFER msg in invite.
and I do manually like
Incoming calls ----Answer on PBX Exten---- XFER to any external number its working.
also I create a custom destination and set this destination in inbound route directly then also its working.
now how to use REFER or transfer call to external number from freepbx via twilio with refer msg.
Thanks in advance.