Bad service

Get sms says account not paid but has been paid. It was apparently short paid by R8. Didnt get statement etc. When try to call RCS or whatever the call centre is they ask all questions then say hold on checking account. ON cell fo r15 mins and call drops. So i call back. New agent and have to verify all over again even though she said call recorded. Then also goes away to check and hold on again over 10 mins. Also account is interest free and now i see interest added to account which only has balanc of under 400 rand and I pay installment in time.