West Bengal State Electricity Distribution Company [WBSEDCL] — Need refund of security deposit money given while installation of meter

I have installed my electric meter in 2008 and deposited the security deposit money with WBSECL however now i have sold my flat and want to claim back the security deposit money. When I have asked the electric office for the procedure, they informed me to bring the deposit slip which I have received before 13 years otherwise I will not receive the same. I said the same has been misplaced hence there should be alternate procedure since this can happen with everyone. They inform that no refund will be given unless we have a copy of security deposit which was give 13 years ago and are very rude.

Let me know the alternate procedure to claim the refund