Balance/ Amount due

I am very angry for truworths taking me for a fool and consultants that have answers, I called the previous month to reduce my credit limit to 4000 and advised I did not want any extra on the amount to buy, I received an sms saying I must 830 and I am on 6 months that doesn't have interest I was advised I owe 3469 only so why must I pay you more than a 1000 I need an explanation and the consultant advised because I bought but still doesn't make sense amount to be paid must be equal to owing since it doesn't include interest I am very disappointed on the ******* going on that they don't have answers to and I feel so angry I am going to close the account