Cheque withdrawls problem

Hello Sir/Madam, I have a tenant in my building since the last 7 years who is partially blind and is survived by his wife and a 8 yr old son.. The person is a real estate broker and very frequently buys and sells lands or properties.. There has been instances of me helping him to travel to hospitals, sites, ATM's and Banks when needed as he cannot manage himself all alone.. There has been instances where in he has requested me to withdraw money from his bank for his use medical n other expenses.. During such times he has mentioned my name on the cheque and I have withdrawn and given him the money on many occasions, I do not have accounts in his drawer banks.. it's a cheque where my name is mentioned and banker is advised to pay me.. To my utter horror and disgust I'm shocked to recently see a complaint by him telling he paid me the money to buy the house which doesn't even belong to me, his health has detoriated in the recent past and the entry of third party family members have come up with such an idea.. I have never used the money nor do I have any transactions with him apart from just helping my tenant on humanitarian grounds before 4 years and now recently he had come up with a plan that he paid me money towards buying the house.. please advise.. this is really unfair..