Company doesn't care about thier customers

I had my account with Mr price for more than 10 years and I have been paying my account every month last year December went to go pay my account I was only owing them R99 when I get to the store im owing R1200 how they said I bought airtime I have never bought airtime with my account then log a dispute for my account submitted everything no one bother to call me regarding the dispute but they will call me to say I'm owing them this clearly shows that our information with Mr price is not safe they not following POPIA now they handed over my account to Debtors my question is why?? People are using our accounts *****ulent and Mr price just handover customer accounts without investigation