I've asked a Comcast employee to help you. You should expect a reply in this thread.
Hi Beavers1, I would be happy to look into your missing equipment for you. When you went to the store and returned the equipment, did you get a receipt? To look further into this I will need to verify your account information, can you please send me a private message with your full name, street address, and account number by clicking on my name (ComcatsAmir) and then "private message me"?