Mis-selling of contracts

I signed up with Mondo in December 2020 when I spoke to a consultant: Daniel Naidoo he ensured me that the service he was offering me was for R150 per month for 20g and it was capped. The next thing in January a debit of about R400 went off and in Feb R300+ went off in March I cancelled but they kept on debiting. The account is now in arrears and it's messing up my credit score. I spoke to mtn and they told me that Mondo would settle the bill as it wasn't what we agreed on, they still haven't settled the bill and I need it settled as soon as yesterday