Only Adobe could help, they have to reset the count (if they agree to). It will now be very hard to get this done because Acrobat 8 is long ago out of support, but keep trying the CHAT.
I have an attorney who is willing to proceed on a class action suit against Adobe for unilaterally deactivating older versions of Acrobat and other products. I do not want to go this route as it will be a simple fix, but if Adobe persists in this fraudulent behavior, it is the best recourse. The deal is that until Adobe is hit in the pocketbook, they will try to cheat purchasers out of their older licenses, which licenses, by the way, do not give them the right to deactivate the product without the purchaser's permission. This will not be a long, drawn out process as it is an egregious breach of ethics and contract. I would strongly encourage Adobe to head this off by providing a method to reactivate our product licenses; otherwise, this is going to get ugly, fast!!!!!
Your premise that Adobe is unilaterally deactivating older versions of Acrobat and other products is based on what?
Adobe is certainly not doing what you claim, i.e. deactivating valid perpetual licenses to Adobe products. That having been said, if someone unknowingly buys a term-limited license from some unscrupulous party (not an authorized Adobe reseller) believing that they are buying genuine product, yes, products will be deactivated when the term has expired. Similarly, if a license code has been found to have been pirated or otherwise misused, products can be deactivated (examples, someone buys a bulk license and license code for same and against the terms of the license, “unbundles” that license, illegally selling that license and code to a large number of customers who believe they are buying legal, end-user product — such product is often hawked by shady vendors, often on eBay and sometimes even via independent vendors on Amazon, as “OEM versions” - something that really doesn't exist!).
Customers who buy genuine product from authorized Adobe resellers simply do not have their products deactivated.