Kotak Mahindra Bank — ECS cancellation charges

I had taken a loan of 3000 from a financial company other than my bank in 6/2/2021 and until september 2021 the ecs has been returned 19 times for emi's of 73 and one emi of 3200. the bank just deducted 11385 from my account for the cancellation of ecs charges. thi smoney was for my college tuition fee i would like a refund for now. even if the bank doesnt want to waiver my charges fully or partially i could sign a bond declaring i owe them the money and pay them within a period of time. Please resolve my issue