MTN

I renewed my data contract with MTN as I was paying R199pm for 40gig,so as the new contract as stated on it,to my surprise Mtn deducted R2400,00 in June,R1200 July,R1200August even if after I complained, complained and they noticed their mistake and corrected deduction to R199,and asked me to send proof which I did but till today am still waiting for my refund,I complained to ICASA in which they intervened but still waiting,even after they told me their billing department made mistake but it is difficult for Big company like MTN to refund R4000,00 to loyal customer since 1999