sale of vehicle that has been veridoted

i sold my vehicle a Peugeot 107 in july 2015. i purchased this vehicle from pinetown cars in June 2013. upon sale of said vehicle the licensing department, police department and road worthy have informed me that this vehicle has not only been in an accident previously where by it should have been written off, but the engine is also not the original engine. they have now impounded the vehicle and have requested that i take action against pinetown cars in regards to all the above mentioned matters, if i cannot pertain a tax invoiced stating that the engine had been replaced by them and siting for which reason said action was taken.<br>