HP India — service center not responding

It's been 20 days, since i gave my laptop to authorized hp service center for repair. They told me it will cost around 7500 rs and they will return the lap in 2 days, but it's been 20 days. The never call back and every time, i call them, i am getting the same reply, (We are yet to get the spare parts). Hp after services are the worst one. The treat their customers just as #.