Unlimited Data "Temporarily Unavailable"

I had the $30/month unlimited data plan with my own equipment for most of the year. Last night I got an email which informed me I had used 75% of my data limit. I checked the Xfinity app and found that I was somehow back on the 1.2TB limit.

I have tried via the app and the website to add the unlimited data plan back to my account, but after a page that says it is adding to my services, I end up on a page that just says that it is "Temporarily Unavailable".

Please tell me how I can get my unlimited data plan back.

Thanks,

Jason Rush