Cholamandlam Finance & OBC - Cholamandlam Finance company Oriental Bank of Commerce cheated me

Respected Sir,
I want to lodge a complaint jointly against Cholamandlam Finance company and Oriental Bank of commerce.Sir i bought a Mahindra Supro Van in January **** & got it financed from Cholamandlam Finance company.Sir there after i am regularly paying installments of loan to Choamandlam finance company through internet banking on due date.Sir this month in feburary **** Cholamandlam finance company tried to withdraw the installment through ach from my bank account.Sir,i have never authorized Cholamandlam finance company for ach although they took my bank account details while financing the vehicle. Sir it resulted in rejection of ach as i was not having enough balance in my account.Sir,my bank Oriental bank of commerce charged me *** rupees for ach rejection and Cholamandlam finance company charged me *** rupees for ach rejection.Sir even my bank did not contacted me to enquire if i have authorized Cholamandlam finance company for ach. Sir when i contacted Customer care center of Cholamandlam finance company,i was told that every time since they have financed the vehicle they are collecting the loan installment through ach ,which is not true and it can be seen clearly in my bank statement that always installment has been paid by me through internet banking.Sir when i contacted my bank i was told that it will not happen in future but this deducted amount will not be credited back in my account.Sir,kindly take a strict action against cholamandlam finance company &Oriental bank of commerce so that they can not cheat me in future & to some one else.