You'd have to contact A & G Software Store about the license number not working I'd say, as you have proof of purchase.
- Check with them WHAT type of license you purchased, and for which operating system.
- Is it a Lifetime license? (you download software, install and will be asked to enter serial number)
- Is it a Subscription license? (you install Adobe Creative Cloud desktop app, and install the software from this app).
I can't vouch for them being an authorised Adobe product reseller, however seeing mention of downloading RAR files and super low pricing, make me wonder if they are entirely legit, but I could be wrong. Also in checking their Refund Policy 'downloadable software products' are non-returnable.... so once purchased no money back...
You could also try contacting Adobe customer support WITH your proof of purchase / license number to confirm you have purchased a valid license as well.
(see the bottom of this page: Plans and pricing | Adobe Acrobat DC which incidentally allow shows you the retail pricing for Acrobat DC as a comparison to what you might have paid, as well as gives you access to Adobe authorised resellers of the software).
They'll likely want to know the following information:
- Where you purchased the software.
- Your license/serial number.
- Your Adobe ID (email address).
- What Operating System you are using as well as the version (e.g. Windows 10, Mac OSX 10.12 etc.)