It can be confusing. There are a variety of different "new" statuses. The "Refer a Friend" codes don't care what level you are; they care whether you have subscribed yet. So if you've already added subscription time to the account, then it is too late for a code indicating you have been referred.

You can, however, still receive the fist bump emote (and even more than you would get as a referred player) by referring another yourself (if by chance you have a friend that doesn't yet play or something).