Maybe the lender forgave the balance of your mortgage loan. No, that can't be right.
Maybe a rich relative paid off your mortgage loan. No, that's not likely.
Maybe, just maybe, and this may be a long shot, call the lender; they may, and I understand that this is hard to believe, be able to help you.
Yes, the more I think about it, call your lender. What?? You don't have old bill to use for phone number. Well, in that case, I think you need to get some HELP.