Motor vehicle accident claims related issues

Sir, I sold my vehicle on [deleted] to another person, name him X. X again sold the vehicle to another person Y. Y again sold the vehicle to a person named Y. During these transaction, the owner's name was not changed and the vehicle remained on my name. the vehicle hit a person while in possession with the person Y. MACT case finalised with direction to pay the compensation by the RC holder of the vehicle, ie, by me since the ownership was not changed to Y in the records of RTO. I had not appeared before the MACT during the case. The vehicle was sold on proper agreement on a stamp paper. Please advice, whether I am liable for payment of ompensation or by the actual owner, i.e, Y who was the owner of the vehicle at the time of accident though the owner's name was not changed in the RC book. What is further legal remedy available to contest and prove my innocence? Who is responsible to get the name changed in RC book, i.e seller or by the buyer? Is there any similar case judgement/ order issued by the High Court/ Supreme Court available with your goodselves, and if so, please mail to me a copy of the same for reference and defending my case accordingly ? Your valuable advice is awaited