Iphone 15 pro - trade in program. Did you have any success?

Very frustrated with Xfinity mobile's trade in program. I ordered two iphone 15 pros when it was first released with their trade in promotion of $830 credit for my iPhone 13 pro. I received my new phones and mailed in my old phones which arrived based on the tracking numbers before the trade in deadline, which was Oct 12. It's now Dec 14th and I still haven't received my credit and there is no acknowledgement from Xfinity that the trade-in devices were received. Based on the tracking numbers, both phones were received by Assurance (their partner program for trade in devices). 

Beware of Xfinity trade in programs, do it at the store if at all possible.