Activated modem under wrong account

I purchased a new modem to be set up at my mother's home to replace her current one. I downloaded the app, logged in and activated the new modem. Easy and quick to set up, I was so happy! Happy until I realized that I logged in to the app under my xfinity account so the modem was activated but at my home address!!! It should have been activated under my mother's xfinity account with her home address. I hope my rambling makes sense. I wanted to know what to do. Do you deactivate the modem and reactivate using the right customer account? Help!!!
Thanks