Worst experience ever

My foschini account was handed over to them for collection sometime last to which i was unemployed at the time,however as soon as i got a job i made an arrangement to pay my account in full and they did offer me a 50%discounted settlement offer and i do have my paid up letter stating that my account is paid up,to my suprise there is still a balance that still appears on my credit record on experian.i tried to communicate with them several time but still no change can someone please assist.