Calcutta Electric Supply Corporation [CESC] — ABSURD bill amount & DELAYED bill intimation

Dear Sir/ madam,
We have received a bill on mid-December 2020 for the electricity consumed during the month from July to October 2020 of about Rs.27000/- . Even though CESC sent us electricity bill on May (Rs.67/-), June (Rs.730/-), August (Rs.560/-) September (Rs.1210/-& 360/-). Till September nothing pending.
After huge bill received on December, we contacted your office, but they forced to pay it immediately else threatened to cut the meter connection soon. How injustice done against the consumer is really pathetic.
How is it possible that such huge bill generated showing huge unit consumed? The CESC not even bothered to contact us / intimate us on the June/July 2020 about sudden huge unit consumed. Whereas CESC after nearly 5 (five) months later generated the bill. Generally the room is given rent to bachelor people sometimes. They have left on October and if the bill came within October then also it was possible to get the money/ they can also give explanation about huge unit consumed as per your bill. Which we have never seen such issue before, as there is no addition of any such electric equipment in the room.
We have no idea how it happened and the room is still vacant and since CESC delayed to intimate/ generate the bill for about 5 months, hence being jobless and I am not able to pay the bill of such amount.
Generally delay bill payment attracts penalty from you, then what about CESC sending bill delayed by 5 months? How much penalty we will impose on CESC?
FIY: The bill amount is really absurd, which is seen as per past many years’ bills. Hence we have not got any justification about this absurd huge bill. The same happened for my wife’s flat at Jadavpur, but CESC accepted their mistake and revised the bill from Rs.16000 to 700 amount upon enquiry to Mandevilla cesc office. This is one of the many instance where a huge mistake made by CESC.
Your favourable reply is expected soon.
Note though the room remained vacant now as well as during COVID-19, but I will pay the meter rent for the Covid19 period immediately if you allow me to pay it.
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