I'm trying to create a prioritized hunt group, with external mobile numbers only, no internal extensions. I have extensions setup which are set to ring for 1 second before forwarding to an external number, this bit seems to be working ok. When I create a ring group containing these extensions however, the ring group just shows busy and never rings the external numbers. The end result I am trying to achieve is a ring group containing only external numbers which will work down the list using the rebound function until someone answers and confirms they have answered (to avoid the call going to an external voicemail). Am I going about this the wrong way?