Olx purchase now asking for a refund after disclosing all the details

I sold my used Samsung tab to an interested buyer two days ago. It was two years old from the date of purchase and this was mentioned to the buyer. But the make of the tab (model year) was 2016. In the ad, I mentioned clearly the name of the tab I'm selling, and all the info about the tab is available online when searched with that name. Moreover, when we decided to meet, I told him to inspect the tab before making the purchase and he inspected it superficially. Now he texts me saying that the tab is 5 years old(actually two years old from the date of purchase as I mentioned). He's now saying that the android version is old and doesn't support new apps and hence wants to return the product. I have neither forced him nor lied about the product before he made the purchase and olx has a strict non refund policy, the buyer is supposed to check the product before making the purchase. So in this case, is there any fault from my part? Should I oblige and refund the amount back?