exten => 3709,1,Set(LOOP_COUNT=1)
exten => 3709,n(loop-start),VoicemailMain(@${CONTEXT})
exten => 3709,n,Wait(.5)
exten => 3709,n,GotoIf($[${LOOP_COUNT} > 3]?loop-end)
exten => 3709,n,Set(LOOP_COUNT=$[${LOOP_COUNT} + 1])
exten => 3709,n,Goto(loop-start)
exten => 3709,n(loop-end),Playback(vm-goodbye)
exten => 3709,n,Hangup