Call forwarding

I added on XFinity telephone last week to my account. I had AT&T landline for a long time and have Panasonic phones. I set up call forwarding to my cell phone by dialling *72 as suggested by XFinityand, setting up for trans  fer after 4 rings. However when I tested the system, the calls get transferred immediately to my cell phone when the phone rings. I have now disabled call transfer. Can anyone help?