There was a problem with the API key you entered: "Premium membership expired"

I signed up today for a 1 month membership, downloaded and installed the anti-splog plugin but cannot activate it. I get the error message: There was a problem with the API key you entered: "Premium membership expired".
I did cancel the auto renew on my membership but it says that I am active till 12-10-10. How do I get the plugin to activate?
-Gregory