How do I escalate customer service beyond a representative, supervisor etc?

Back in March I went to purchase a phone and the store did not have the correct color so we had to order the correct color from corporate. When the phone came, it was not the correct color, so we had to get that resolved and went to the store where I was told I needed to call the corporate number for returns and handed a card. I called the number to get shipped me the correct phone and was told to return the other phone. They said they were sending me a return label and I would get it within 5 to 7 days. The label never arrived and I called again after the seven days, we are verified all of my information and email information and I was told it would be another 5 to 7 days. I repeated this process a number of times as I never got the label and all of a sudden Xfinity took $638.99 out of my bank account. I went to the store to speak to somebody in billing and to get this taken care of where I was put in contact with a virtual assistant who finally got me the return shipping label and I sent the phone back immediately we are Xfinity signed for the phone the next day and I was told the return would be 5 to 10 business days. The return never went through Xfinity has my money and the phone. I have repeated this process and going to the stores called the help line and been told a number of times through virtual assistance that the refund was processing and I should get it within 3 to 5 days, here we are months later and I still do not have the refund.

 On top of this when I came in the first time after the $638.99 was taken out of my bank account. I had to upgrade two of my phones and the representative told me that we had a special on our account where we were to get two of the Apple watches for free. I asked repeatedly if it was going to increase our bill at all to verify that they were in fact, and I was told they were. So I accepted getting the watches only to find out with my next bill which was after 30 days from the point that I was in the store that he was charging us for not only the watches but also for two additional lines. When I talk to the virtual assistant about this, he said since it was past 15 days they were nonrefundable and he couldn’t do anything about them. I didn’t even get the bill until after 30 days to be able to see what had happened .