Not getting $10 Autopay discount

This is the third time I'm trying to get this issue resolved. The first two times I tried Xfinity Chat Support, but they seem either unable or unwilling to fix my problem, so I thought I'd give the Support Forum a try.

In short, I'm a single customer, but I get Xfinity service at two separate addresses, so I have two accounts and get two bills every month. Xfinity offers a $10 discount to customers who enable both Paperless Billing and Autopay on their accounts. I have enabled both of those on both of my accounts several months ago, but I've only been getting the $10 discount on one of my accounts and not the other.

Again, I've contacted Chat Support about this months ago, and explained my problem in detail. They apologized, issued me a one-time credit, and said I would be getting the $10 discount from then on. However, my very next bill didn't have the discount applied, nor did subsequent bills. I contacted them again a couple months later, explained everything in detail again, was issued a one-time credit again, and was then instructed to disable and re-enable both Autopay and Paperless Billing on the affected account. I did that, and was afterwards reassured that the discount would be recurring. On my very next bill, the discount wasn't there. I've since gotten four bills without the discount, and am about to pay a 5th, so I'll be out $50.

Is there anything that anyone can do for me?