When you cancel your smrtPhone account, all numbers will be released. If you would like to retain your phone numbers, you must port out your phone numbers through initiating a port request. Once your numbers have transferred to your new account, you can close your smrtPhone account without concern.
Of course, we hope that you don't cancel - and would love to speak with you about your concerns to see if we can rectify the situation before you leave. Please reach out to our team and tell us your thoughts!