Popular Maruti — Service issue

I brought new maruti spresso red color car in December in thiruvalla popular maruti center. First service is over. There not insert the gear box cup. And that service time. They are used my petrol also Now i can't ride with my car. So. Many time i called branch. And head office in kochi. They are not responding. I want solve my issu witu in a week other wise im going to consumer court