Customer Service Email? Chat/Phone brushes me off with something I'm willing to cancel my service over.

I got AT&T service via a promotion. Got two different answers about when I'd get my rewards. Apparently it was sent during the Hurricane Ida devastation (I live in New Orleans) They claimed they emailed me (never called.) My records show I've gotten emails, but not about that. The rewards have 'expired' (One of my answers was 6-8 months before checking back.) It's been 11 months. They keep saying there's nothing in the world they can do, even though the card(s)? were never redeemed, and two different convos with two different agents suggested there was a lot they could do, the other refused to even escalate it. Not my only issue with AT&T, but this is a real bad-faith move. Highly considering cancelling, since my place is already wired for Cox cable. Haven't' even been with AT&T a year and I have a lot of complaints. This one is the most personally insulting. Email for customer service? Chat & Phone yielded nothing but obsrtuction.