Asterisk should not answer when he is not knowing the DID

Hi @all,

I would like to have asterisk to not answer a call in case of not knowing the inbound DID. The trouble is that my SIP provider is signaling two calls instead of on call. One call is comming with the registered numer and one with the sip trunk number. The first incomming call is the registered sip number but this on I do not need. I would like to answer only the second call with the right number.

Asterisk 1.2.24
FreePBX core 2.5.1.3

Thanks
Christian