Something

exten => _NXXXXXX,1,SetVar(FULLCID=CID${CID${CALLERIDNUM}})
exten => _NXXXXXX,2,GotoIf($[${FULLCID} != "CID"]?5:3)
exten => _NXXXXXX,3,SetCallerID(${FULLCID:3})
exten => _NXXXXXX,4,Goto(6)
exten => _NXXXXXX,5,SetCallerID(TDX Corporation <9072782312>)
exten => _NXXXXXX,6,SetVar(CALLFILENAME=${EXTEN:1}-${TIMESTAMP})
exten => _NXXXXXX,7,Monitor(wav,${CALLFILENAME})
exten => _NXXXXXX,8,Dial(Zap/g1/${EXTEN})
exten => _NXXXXXX,9,Congestion