Still no trade in credit

I send in my s23 ultra late March 2026 I have a receipt from the post office & a email from august 19 2026 that my trade in is completed, still no trade in credit so I called i got the run around from a guy that I could barely understand & then he said xfinity can't help put asurion can I said no they can't they are a claims dept that replaces damaged or lost phone he transferred me anyway & the agent there said you are right we can't help you . So they are playing ping pong with at this point what can I do ?