Hero Motocorp — worst service

Address:

Hyderabad, Andhra Pradesh, 500072

I am owning bike number : ap28 dj 8076. Recently i gave my bike to servicing in "hari om motors", jagatgirigutta, hyderabad. While giving they said, need to replace cam chain kit and chain kit. Finally they charged 2800/- for service.
From the next day i observed, engine oil is leaking from the engine part. I took the bike to same service point again. They said oil sil part was damaged and replaced. Not sure how it was damaged while servicing, it was good before service.
Even after they replaced the part, it still leaking the engine oil. Don't know what todo with worst service point.