Indian Oil Corporation / Prasanna Gas Agency — Long undue delay in Delivery of Gas cylinder refills

Sir,
I am a comsumer of Indane gas for the last 13 years. my consumer no. 10848 with prasanna gas agency at padi, Chennai. Last month I received my refill on 3rd May and I booked the refill on 13th may 2008. till 10th of june the refill was delivered despite my several reminders both personally and over phone the agency in charge has not delivered it. Today I took an empty cylinder and hired a taxi to goto the agency to get the refill. Then they issued the refill and gave some lame excuses for not delivering the cylinder ontime. I want to ask the following questions to the Customer care dept.( If it exists?) of IOCL. If a consumer has two cylinder LPG connection what is the refill cycle one should follow? What is the time delay between refill registration and refill delivery if only one cylinder connection and two cylinder connection is there? What if the first cylinder is exhausted and second cylinder is nearing empty and still the refill for the first cylinder is not delivered yet? WHat is the relief for a senior citizen like me who has to go to agency to take delivery of the cylinder every month if no delivery is made by the agency? Whom should I lodge my complaints at IOCL? Is there any consumer forum where I could voice my grievances?
M. SIvalingam