Sorry to hear you are having issues. If you purchase using paypal, usually it will be linked toward your paypal linked email account. Have you check to activate using that email address?
Try that, and if still fail, please raise support ticket using the link below, use the product not received option. Include all information details. Remember to record down the ticket number for future reference if needed. Do not raise multiple ticket, that will make your ticket back to the end of the line. Send once and wait. Ticket will be answer by the order they send in.
Stardock Community Assistant