Arrears

My account is in arrears as I did not pay for the month of December, then In January I was called by Call Direct consultant and made an arrange that the company deduct the normal monthly instalment and half of the arrears amount in January, then Today I called Direct axis informing them that I wont be able to pay the normal monthly instalment and half of the arrears amount just like we did in January and the consultant told me they will deduct same amount they deducted in January, then I told him that for the month of February I cannot afford but he insisted the company will deduct the normal monthly instalment with the outstanding arrears amount, This is unacceptable as I wont afford but Direct Axis insist on debiting my account more money with out my consent, Please assist as I only want the normal instalment to be deducted this month then I'll settle the arrears amount after.