had not recieved the booked cylinder yet

Location/place: uttam nagar rama park road

Name of company/service: raj flame gas agency

i had booked a cylinder on 17 nov 2012 and when i was to check my status of cylinder on 20 nov 2012,they said had delivered.but the cylinder not delivered yet….i have been suffering from approx. 1 month…i went to the agency before but they said cylinder had delivered but i had not recieved that cylinder.please help me m a middle class woman and suffering alot