Hi Reagrding Billing in BSNL there are often billed for different plan without any of your acknowledgement or no request for change of plan. As soon as to file a complaint the first reason they give would be your line is in business area or in firm address so its changed eventhough you use it for homes. Its better check your plan regularly using your portal ID.Always before taking the bill issues gather the evidence that you have used in your exact plan.Using the portal ID take the print out of the plan and usage for the billing period. Also attach previous months Bill if you have(Maximum the issue will be in the Billing section, there wont be any change of plan with out your knowledge) Go to the BSNL office and write the complaint to Accounts Officer, explain to him politely and even contact the Commercial Officer about compalint because CO will only confirm your plan. It will take time (a week or 2) but hope they does favour you. If the plan is already changed in the portal then you cannot argue, we will have to pay the bill and change the plan for the next period. Its very hard to make them know they had made a mistake. Share your experience so others will get out of the problems sooner and make BSNL better.