Debt collection — Credit Protection Association, L.P. (CA)

Debt is not mine. A company called Credit Protection Association has been calling me for the past week with an automated call telling me that I owe a debt. A debt for what I do not know. Even if I answer them when they call ( and they may call several times a day ) all I get is a recording asking for an account number. They ask for an account number that should be listed on a letter, however I have never received any letter from any company by this name. Their automated system also allows to find your account number based on your phone and zip code. However when I enter this number all the recording tells me is that my account is closed. I have no idea what this is about, I just want it to stop.