I assume I am missing a setting. When a call comes in and the caller ID hits my cell phone the caller id says +1 and not the correct number
Your ITSP has to allow the setting of your own CallerID to pass foreign (Not already on the Trunk) caller ID - Make sure they (and you) can pass Foreign CallerID - Sometimes you need to send a pAsserted Identity with your Trunk Caller-ID to allow passing foreign Caller ID in the actual call.