Calculation mistake in KE bill

My bill of k electric for the month of March has several mistakes. One of the mistake is of calculation. There is wrong calculation of charges in the bill. My second complain is, Total consumed units are 330. For every unit either that is below 300 or above 300, the charged amount for every unit is 25 rupees. My third complain is, there is an addition of 12 rupees in the bill for the previous month although we have paid the full bill last month.