Wrost service centre

I am Rahul paradkar from Indore I have nissan dustan redigo car. The car number is MP09WB7578. The Service center name is Hriday automobile pvt ltd. This car oil chamber is a plastic that breaks due. after that my car take to the service centre when they told me 15000 to 16000 charge. After 2 - 3 days I go to service centre they tell double charge 35000 to 40000 and every customer's face this problem. This is poor service.