Brihanmumbai Electricity Supply & Transport Undertaking [Best] — high electricity bill for the month of july

Best electricity bill is very high of month july 2020
As my consumer number is [protected]
Name: satyavati sainath pai
My electricity usage is not much i pay my bill every month.
My last bill was ₹450 for june 2020.
But in july the bill amount is ₹1370.
We haven't used much electricity this moth so how the bill is genrated so much high