Adobe cancelled my Serial # for Master Collection CS6 without cause

The account used to purchase and the email is no longer active. It was over ten years ago and purchased through Adobes education program and verified by Adobe at the time of activation. Of course I can't find the invoice after ten years. The IRS doesn't even require that. But then Adobe is not an American company. 

I am having the same problem. I get this huge notice that repeatedly pops up saying my Photoshop CS6 is an unlicensed version and they will disable it in 10 days. I bought the disk years ago directly from the Adobe website because I didn't want to spend thousands into perpetuity with a downloaded cloud version. You're lucky you still have your receipt, mine is buried with all my tax records and I sure don't remember what year I bought it. There was no indication back then that Adobe would try something this underhanded down the road. I think it is a ploy to get rid of any option but a subscription, but it is a nasty disrespectful way to go about it. Regardless, I could not get any help online. I have my serial number but they want a proof of purchase. Since I bought it from them I would think they would have all that information. Just know you're not alone on this one, and if anyone has any information on what to do - within those threatening 10 days - please let us know!!!

from whom did you purchase?