Kotak Mahindra Bank — harassing me

Address:

Chandigarh, Punjab, 160002

Hello
I availed a finance facility from kotak mahindra bank. Last month i missed the periodic installment and next month i filled the two installments together. But without any checking they started calling me up i told them many times that i have filled the installments but they behaved very rudely and i started arguing them. After that what they did they deduct rs 1520 without any reason and when i asked them about the deduction they were unable to satisfy me, i called them many times but all in vain. Last week they send me a letter that some installments are due but i have payed all the installments on time. I called them but now they’re not answering me. So i have written to their higher authorities and waiting for their reply.