After you pay, you should get a link immediatly after from the billing page to associate your forum nick with the payment, then a link confirming your profile (double check the profile thing, I found some things wrong, I think they make some things wrong so you will set it right and then confirm it), then a final link will activate it. Email the subscription email thats mentioned at the top of this forum, it takes a day or two for them to respond unfortunately, but they do eventually. I had a similar problem myself, but eventually got it activated.