I dont know if what I'm about to say fits your case or not .... but ....

On the 29th of may, an article was published quoting someone from SE saying that CE purchases would not be usable to upgrade "pre-existing" accounts....

This is a situation that is biting me in the arse right now, and hopefully not your case as well ...

For two reasons, one it's dumb as H*ll and two, it is cheaper to upgrade an account to CE from the MOG station. So now I'm going through the LONG and drawn out process of working out a refund so that I can now "properly" upgrade my account.

The CE purchase from SE's site has to be applied to a bran new account that is being created for the first time .... very lame advertising and very poor merchandising. There should be red lettering all over this problem when you are ordering ... but there is nothing.

Hopefully this may not pertain to your case.