Hello together, I would have asked a question and I sold my vehicle and the gentleman who bought the vehicle was satisfied we have concluded the purchase contract now he says to me that the vehicle has environmental badge Euro3 instead of Euro4 and claims that I have stuck this on it although the previous owner where I bought the vehicle at that time also drove with Euro4 and I registered the vehicle and handed out the green environmental badge Euro4 at the road registration t now he wants to give the car back and says that is in Ebay mini-indicator Euro4 and in the purchase contract I have not noted what for pollutant class and environmental badge the vehicle has but the buyer has finally seen the vehicle license and in the vehicle license stands Euro3 and now he says because I allegedly made false information, I showed him everything during the test drive and on the windshield is the Euro4 badge, I am obliged the car to return k increase although in the special agreement in the contract no guarantee etc(what should all be in a private sale contract) he is right that I have to take the vehicle back? I ask for a feedback.