Account instalment not reflecting

I have a Edgars account on the 21.07.2015 i went to Edgars Red square in Auckland Park to pay my monthly instalment of R 900.00, I was assisted effectively however the amount that i paid in did not reflect on my account , i went back to Red square store to query the payment .The store Manager requested proof of payment i provided the proof of payment, After that the Manager check the payment on system and it was not reflecting she then called accounts department they told the Manager to fax the proof of payment, The Manager faxed the Proof and i was told that i will be contacted for feedback . I waited for feedback on what happen with the instalment and i did not receive feedback i went back to the store and i was told the store Manager who was assisting with my query was off that day. The collection department started to call me asking when am i going to pay the account i explained to them what happened and on the 21.08.2015 I went back again to the store telling them my query was still not resolve, the manager phoned accounts department again she was told to fax again, up until now the payment is still not reflecting and interest is added on arrears amount and no feedback.