Xfinity owes me a refund and has still not done so!

This has been an ongoing issue for more than a few months. I moved way back on July 31st. I did the right thing by putting in my move out date the day before, and my move in date as the 31st. Yet, Xfinity billed me twice, once in August and once in September. I went into the local Xfinity store, and we cleaned up the mess that your own tool caused. However, I was told that they could not offer me a refund there and that I had to call in. When I called into support, after being on hold for well over 45 minutes, they tried and could not understand the issue. I gave up and tried chat support. I finally got someone to understand what the problem was and was promised a full refund. That never happened.

I finally submitted a refund request and this was also refused. At this point, I need someone to understand that I am owed money. I have the proof. And to have to go through this much effort to do this is beyond dumb.