Olx purchase

Hi, I don't exactly know under which section my query falls under, so put it under civil law. I sold my two year old Samsung tab to an interested buyer two days ago. He had asked me how old the tab is and I mentioned two years.This two years is from the date of purchase of the tab. But actually when you see the model year of the tab is 2016 which is 5 years old. He had asked me that he wants to see the tab before purchase and we decided to meet in a public place and he inspected the tab superficially and said okay. Asked for any defects and I said none, as there were no defects. After two days, he texts me saying that the tab is 5 years old and not two years and that it doesn't support new android apps as its version is old.But actually it is only two years from the date of purchase but 5 years from the model year. Also I've clearly mentioned the name of the tab so he could have checked the details of the tab online or even before paying me the amount. So according to this, I don't think I've done anything wrong...but he's asking me to take back the tab and refund the amount. I don't know if I'm wrong from my side and how should I go about it...