wrong billing and cancellation of multi sim

i have been asking for my multisim to be cancelled for 2 months without luck ( case no. ***5 )<br> my contract always got wrong billing with old contract expired 2 years ago , they keep on billing me add on and every month i have to call to query my billing this is frustrating ( case no.***2 )<br> <br> please reslove this i am tired of calling every month .<br> please cancel add on my new contract cost R199 + 69 mediapad only .<br> i also asked to cancel cli on mediapad