My telephone no 033-25422014, my broadband connection was from 29/12/2007(18:58:46)under BSNL Dataone home paln 250 (1GB free downloading & uploading)on the the basis of annual subscription of RS-/2500.Now in the month of Agusust I have applied for BSNL Home Combo Plan 500 (change from 250 to 500c)annualy. According to BSNL tarrif home 500 c gives 1.5 GB free downloading and uploading and night limit free (2-8 AM)in month. So BSNL changed thier plan for my telephone on 26/09/08(1903). Thier customercare told me that they will adjust the amount with earlier paln. I started downloading from 26 sept at night(2-8 AM). So my downloading was 8.891Gb (Recieve 7.219 GB, Sent 1.672 GB.)and excluding night unlimited was 1.072 Gb according to their portal address of 10.240.89.199. On 16 October they send a bill issuing "Broadband Usage Charges - Sep-08 = RS/- 7272.00". So pls tell me what can I do ...