What a mess...Xfinity Mobile: iPhone 15 Pro Plus Upgrade

I'm not sure what has happened... here's the short of it. 

I responded to a promotion to upgrade my iPhone 11 (which I purchased new from Xfinity Mobile some years ago). The representative assured me that she processed the order as a trade-in, she took my IMEI for the old iPhone 11, and processed the order. A few days later, new iPhone delivered. I activated it, etc. I could not locate instructions on processing the trade-in to get the bill credits, so contacted them again. Come to find out, the representative processed the order wrong; not as a trade-in, but as a new order...

In order to correct it, I was told I needed to return the new iPhone 15 via FedEx. I processed the return and brought it into FedEx. I spoke to customer service to get my old iPhone 11 back on the network, and start from scratch. For some reason, one of the representatives blacklisted my iPhone 11 and noted it as lost/stolen. Now I cannot get it active on the network. A ticket was started, but with no estimate on when or how it can be removed from the black list. I'm now going on day 3 with no active line. I have no way to communicate with children, family, work, school, business, etc. All of my MFA accounts are connected to my phone number. So I cannot access banking, billing, etc. My mother is in the hospital, my father has memory issues, and there's no way for them, or caregivers, to connect with me. 

Every representative I speak to is baffled. They all say, "What did they do to you?" I have no idea how to proceed. I've spent 7 hours on the phone, 2 hours on chat, 3 hours in the store... no one can help me. They all end up chatting with their "advanced chat representative." No one seems to be able to resolve the problem. To reiterate, they created the issue, they worsened the issue, they have no resolution planned..

The worst part is, every time I call, the representative reads their line, "We see you are a long time customer, we appreciate your 8 years of loyalty... blah blah blah..." and then the loooooong "support" ends with no resolution. 

Any others in this situation? Any advice?