Collections Dept Rude and Unreasonable

Wesbank collections division called me today regarding a returned debit order in October 2017. Prior to, and since the missed debit order, I have continued to receive statements and making payments diligently (38 months payments made and only 1 missed). When I asked the consultant why they only contacted me today for a missed payment she rudely responded that she had been trying to call all thjs time and maybe I only decided to answer today. This is a work number so I ensure that I never miss a call. I called her out on her attitude but she brushed me off and said she wants to proceed with the payment arrangment. She then refused to accept the offer I presented of including the outstanding amount of R5007 over a 5 month period, with the normal installment. She then proceeded to tell me that I will be charged an additional R500 for each month that I am in arrears for thst single installment, to cover the collections fees. This is outrageous. I told her as much and hung up. Is this in line with the NCR??? Wesbank should treat their clients more respectfully!!