Unresolved months long issue with credit for turned in phone

My daughter got a new phone 1-26. We talked with an agent on the phone directly to do this. New phone received in the mail. Old phone was sent in received and credit issued. We never asked for a new number. That agent assigned a new number. We did not realize this until along the next bill an email was received to set up your phone with the new number. We were shocked as my daughter never had an issue using her current number and making texts and phone calls with the new phone. The old number was just there. As a result the new number created a myriad of issues. 

Then the trouble began. I ended up chatting with Xfinity to get that number removed and everything put back to her old number. They were able to resolve that but the credit isn’t showing on the new number. The new number is still showing on our bill and that is where we are being charged for the new phone with no credit for the turned in phone. The old number is still on the bill at $0. I have texted and been to the local xfinity store at least 6 times to get this fixed. Probably around a dozen or more tickets have been issued. I have spoken with the assistant and store manager at the local xfinity store several times. They keep saying they are submitting a ticket for escalation. A couple of monthly credits were issued by the store to cover what would be the credit received for the old phone being turned in. This is still not resolved and now I am getting angry. I feel foolish every time I go to the local xfinity store to say this still isn’t fixed. I cannot fathom how this is so difficult for your department to fix. 

There are so many more details to this but it’s so jumbled in my head with all the trips we have made to the store and waiting for a resolution. 

How would I like this to be resolved?

I would prefer to be discuss this over the phone with someone as high in management as possible to get this finally fixed. I feel extra compensation should be offered due to the amount of stress, time and energy that has been devoted to fixing this. I have put off dealing with this at times because I get too stressed.