Car sold via dealer – new buyer has questions

Hello! About 2 months ago I gave my used car in payment when buying a new car. The car was then probably forwarded by the dealer to another dealer (“purchaser” which has now obviously sold the car. The car given by me in payment (VW Golf IV) has been regularly maintained and has m. E. – I am not an “auto expert” – no obvious flaws, which I would have tacitly concealed. Now a letter of the new owner reached me, de The new owner has approached me with many questions. Little surprising he wants to have some information about the acquired vehicle, e.g. repairs carried out, defects that I have already noticed, there is allegedly a Macke on the rear bumper (of which I don’t know anything), alleged ambiguities with regard to the km stand at the timing belt change (this has been carried out in a VW specialist workshop; evidence is available). r uncertain how to react to this letter: On the one hand, I have nothing to blame myself for any hidden defects, on the other hand, I am very surprised that the new owner approaches me after (!) the purchase and wants further information. Therefore, my question: Can/May/Should I react to this letter – or can I possibly get into a situation in which I have to fear legal consequences? Of course, I know that I do not have a contract Westfalenblitz (Germany) and Westfalenblitz (Germany) have given the car – of course – in payment. Maybe you can give me “relevant” hints on how to react … Thank you and best regards Westfalenblitz