Comcast Cablevision Inc. Xfinity Harassment for the return of equipment I own Philadelphia Pennsylvania

In March of 2011, my husband and I purchased a router and modem from Comcast and began Internet service with this company for our Atlanta, GA home. In April of 2013 I cancelled service due to an impending change of duty station. I was asked at the time of cancellation to "return equipment". I explained that I owned the equipment and provided the person on the other end of the phone the receipt and order information. I consider the issue resolved. I have been receiving phone calls asking for equipment return for the last 5 months now. Many of these calls come at absurd times of day despite my repeating over and over that I am living in Hawaii. On September 6, 2013 I received yet another of this calls. After more than an hour talking with the customer service representative the call ended with me faxing a copy of the receipt. Today, September 12, 2013 (at 3:00 am) I received yet another call asking that I return the equipment that I OWN. Furthermore the company owes me $59.21 and I still have not received this refund.