Chat may not work. The 800-AXP-EARN should be the number to call. I do not believe they will give you any issues.
The rep I spoke to tonight said they were having technical issues and that he couldn't get through to the rewards department. I called the same number and got an error message as well.
I was still able to redeem my last batch of reward dollars, get confirmation emails, get the rep to confirm on the call that they'll send me a check for the balance, and close the card.
On the bright side, I probably shed 10 lbs this Thanksgiving