2.1 The opposite party No.3-M/s Aryan Ispat and Power Pvt. Ltd. executed an agreement on 23.04.2005 for supply of power for a contract demand of 1150 KVA for a period of six months from the date of supply from 01.03.2006 till 31.09.2006 and thereafter 3000 KVA with effect from 01.09.2006. However, inadvertently by clerical error, the bill on contract demand of 1150 KVA was made till 31.07.2007. On detection of such error, the bill was made with a contract demand of 3000 KVA from August, 2007. The opposite party No.3 paid the bill without any objection and prejudice. Subsequently, the differential bill on contract demand of 3000 KVA of Rs.32,63,541/- was raised for the period from