Please check who you are calling

So, a dude calls me and he is like, my account is set up wrong. I have an account that I paid for for 5 years with xyz options. I tell the guy that is not possible, because we dont sell 5-year accounts. Our maximum payment period is 2 years. He keeps insisting that we sent it, and reading off account numbers that are not ours, usernames/passwords that are not ours. Finally, he goes, "wait, you are not XYZ company. Oops." That's why I answer the phone with my company name, idiot. LOL