Toyota — innova crysta car damaged during servicing

Subject: Car damaged while servicing
My car Innova crysta Up 73 N 1088 was given for servicing and claim on 5 November to Allahabad service centre they hb ave delayed in returning the car as well as the car met with an accident by them it is badly damaged specially the bumper bonnet and scratched all over on driver side On top of this they are not ready to give the claim and are misbehaving .I needed the car immediately as there's marriage ceremony at my home
Kindly take some action against them and see to it. Obliged.