If you bought it on eBay, then the license was probably used and registered to the email address of the seller, so when you email customer services, that's why they've never heard of you...
If you ask to resend the licence, it'll go to the original email address, or not be done because your email address is not recognised.
Try to verify it, but I think you'll find that you can't use it, and have wasted your money.
regards, Gizbar.