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

I signed up today for a 1 month membership, downloaded and installed the anti-splog plugin but when I added the brand new API. I get the error message: There was a problem with the API key you entered: “Premium membership expired”. Fix it here» It directs me to my API page which is where I found my new API. Please tell me what to do!