What version of Premiere Elements are you using and on what computer operating system are you running it?
For now I will assume Premiere Elements 12.
If you are sure that you are entering the serial number (xxxx-xxxx-xxxx-xxxx-xxxx-xxxx and not a redemption code or something else, then Adobe via its
Adobe Chat is the only one who can help you.
Please click on the following link. Contact Customer Care
I have it pre-set for
Adobe ID and Signing In
Adobe ID, sign in, and account
I do not know if the web page set will hold my setting. If not, you will have to navigate through it to the "Still Need Help? Contact us" until you
get to the Chat panel to click on.
Please let us know the outcome.