Home choice theft

I was paying home choice every month and my outstanding balance was R454 which they called me and confirm that I do owe that amount,so I payed them R460 then they sent sms that they received my money but my outstanding balance now is R1.49 and then I did pay R 2.they sent me sms again saying they received R8.90 which I don't know where it comes from cos I never payed them R8.90 and saying I now owe them R7.07 and then payed again R10 but they didn't even sent me sms that they received my money.now they busy sending sms that I owe R7 and if I don't pay before 10 sept am going to pay R 213 month end.I sent them emails but they dont respond me,my worry is how can I pay them if I settled down my balance with them .home choice people are ******