If her phone was anywhere near wi-fi she could still use it,if she ran away.
I hope they made mom pull up receipts for the minutes on the phone, However is it possible Cassie's trac phone minutes are refilled every month by the state paid cell phone plan?
The the only way I see cassie losing her number that quick..it used to take 3 months to loss your numberis.. If her plan the is safelink thing once the phone was reported lost/stolen/missing if they shut it off and mail you another cheap one for a fee which you can tranfer to a better phone . I know Cassie's mom needed a new phone.
I dont know if this is the case or not but if it is the maybe the minutes refill automatic which one might choose to share or not..