Indane / Gas Cylinder — Refilled gas cylinder not supplied

I have got a gas connection from an agency in Trivandrum ( Shelly Gas Agency). I have booked for a new cylinder on 9th March. The agency has not supplied the gas till date. When i call the office they are giving the excuse that my order number is not reached. I have no option to know if they are saying the truth or they are selling gas not in the booking order. Could you please let me know what i can do in this case