Arrears increasing by R3043.02 in one month??

Email sent 05 August 2015: I would like to know why my arrear instalments has increased by R 3043.02 since the 02nd of June 2015.My End date of my 36 term ended on the 01st of June 2015. i do have arrears and as stated on your statement arrears amount R 2170.30 and on the 8 July 2015 its R5213.32??? So Much? <br> After i called and followed up being told18/09/15 to go into the branch sat there 2 and a half hours today 19/09/15 was told it don't look right..I get the below email 19/09/15: Dear Ms Johnston: Our ***<br> Please be advised of the following:<br> 1. The Agreement between yourself and Lewis Stores has been entered into in terms of the National Credit Act, and as such is subject to monthly charges of Interest, Service Fees and, if selected by the consumer, Customer Protection Insurance.<br> 2. A copy of the \state of account"which is self-explanatory is attached for your perusal.<br> 3. We are therefore at a loss to understand the basis of the calculations made by yourself with regards to the account.<br> 4. We suggest the store manager be contacted on *** in order to schedule an appointment for further discussion and reconciliation of the account.<br> """