As a last ditch effort you can google the CEO's email address and contact the CEO. It's their office who actually answers, but sometimes you can get a resolution you can't get from regular customer service.
I used my Chase Sapphire points on a flight and closed the card afterwards (around the time the fee went up significantly). This was in 2020 and the flight ended up getting cancelled. They returned the points, but my card had since been closed. Customer service said there was nothing they could do, but someone online suggested I email the CEO. A couple of weeks later, the CEO's office contacted me and moved my points to a different Chase card that I had.
It's worth a try!