Hi, I am using bsnl broadband from last 3 years (from may 2008). In april 2010 I had applied to change my plan from Combo 500 to Combo 900. In new plan ie Combo 900, I was given free 400 calls plus Unlimited usage.

But I dont know how after few days like on 15 April the records of BSNL were deleted that I had changed my plan. Now since then they are giving me bills according to limited combo 500 plan.
I have complained thousands of times but no effect. I have not paid any bill since then.
I have complete proofs that I had applied for Plan change (verified even by SDM BSNL Ambala Cantt).

Now they have given me bill of more than INR 17000, which should have been less than INR 8000.
Please help me out. I'm frustrated.