Hello, I have a MagnusBilling server to manage SIP accounts and I add these SIP accounts as a trunk in Issabel
I noticed that every time a call receives a SIP 503 response (Service unavailable) it only passes this information to the Softphone/Telephone but does not display any audio message informing that the call failed
What do I need to do so that every time I receive a SIP 503 response, my Issabel (Or MagnusBilling) handles and forwards a voice message to the phone/softphone?