Tamil Nadu Electricity Board [TNEB] — Ebill amount issue

I got August bil with amt 3389/-. But I didn't use 740 units. I gave complaint to EB ofz, Guduvancherry. Lineman came and just checked house and said it's going correctly. Once again I gave complaint and two linemen came and checked the meter box and said running correctly. Meter box is problem. It's running fast in my house. Single fan if run in meter box red blinking fast and unit running fast. I took video of meter box and shows in eb ofz. After 1and 1/2 month they changed meter box. New meter box running correctly. August bill fully I paid. Meter box problem they didn't reduce amt. For bill duration of this October month - already more than 40days units went more than 200 becoz of this old meterbox. I didn't use anything for 240 units. Meterbox running fast as I already said. New meterbox units mentioned as 70 units. From EB ofz they said we will reduce amt becoz of meter box problem. But they didn't do anything. Now I bill for 639/-. Without usage last bill I paid 3389/-. Worst service providing in Eb office Guduvancherry. Now they are asking to pay bill without any deductions. Behaving rudely. Pls take some action.