Courier Not Received

I have booked my courier through First Flight from Kankarbag, Patna. The parcel is booked on Date 2o/05/2014 for Supaul More than 72 hours have gone but courier is still awaited.
First Flight claims that it will deliver the courier within 48 hours, but in reality its not happening.
My Docket No is – U991M0012475. Please take a strict action against them.
Shantanu