Problem activating Bitdefender

My Bitdefender says "Your subscription has expired", even though I've used the activation code. I used the code in the program itself where it says "Add subscription". It confirmed my subscription, but it still says that my subscription has expired. So I tried activating it in Bitdefender central where it says "My subscriptions", but it tells me "This key was already used to generate a subscription."

Thanks in advance!