Lost/Stolen Trade-in

I recently moved from T mobile to Xfinity and took a new 17 pro by trading in my 13 pro for 1100$ in credits. I then shipped my trade in device to assurant using the shipping label I received. It was stuck at a USPS location for days and it never moved from there. I've been trying to get Xfinity to fix the issue and all they do is promise to look into it, promise refunds that never come, and more delay tactics. 

USPS has labeled it as lost after it spend months trying to "find" the package. Is there anyone at Xfinity that is even able to do anything about this?