Foschini is taking my money

I have a Foschini account which I pay on time every month. I noticed that I was in arrears which I could not understand because I buy for less than my available credit and I pay more than my required monthly installment, which is now R1145.

Yesterday, 24 March 2020, I went into the store to sort out my account and i noticed that i only had R1250 credit available and i haven't been buying anything since October 2019. My credit limit stays the same and I'm paying R1600 every month.

I got to speak to their customer service office, a guy named Ashwin and he sounded more confused than i was and told me that i changed my payment period to 18 months which i did not. Last year I requested that they stop increasing my credit balance without my knowledge or consent. Seems like they changed my plan from 12 to 18months without my consent as well.

I was on the phone with this Ashwin guy for more than 20min. He put me through to another department which he said will assist me to change to 12 months, after holding on for another 5 min, the lady came back and told me that he was supposed to assist me with it because it's not done with their section.

I dont understand where the money that I'm paying is going every month because the total credit amount is not reducing.