I was given pre-owned Xfinity Home equipment. Am I able to use my Xfinity account on a pre-owned Xfinity Home Touchscreen?

I just bought a house and the previous owner left their Xfinity Home Security equipment for me to own. I was able to link the Cameras to my Xfinity Home app. However, on the Xfinity Home Touchscreen, the previous owner’s account is still showing, and I am unable to logout. Is there a way I can log in with my Xfinity account to the Touchscreen so I can view my cameras on there? I don’t have the Home Security monthly service, but it’s my understanding that this equipment should work without the service. Any help is much appreciated.