MTN BILLING FOR DATA USED/ Part One

I have been a loyal MTN contractholder since 1993 with myself, 2 daughters,my wife,one Samsung tablet and a 2GIG date ****le account which i pay via debit order every month.I have uncapped WIFI at home for my wife and daughters useage.My 2 daughters are on top-up account (They get free sms,data and R200 free airtime on their package.Both accounts have R1200 airtime on (R200 can be carried over for 6 months)<br> My phone is the only phone that would go over its free airtime minutes.The ****le that i have i get 2 GIG free monthly that can be carried over for only 1 month,yet the amount of data available is 4 GIG,the max available.My Monthly bill for all is in excess of R3000 per month.<br> <br> On the weekend of 26 September my daughter informed me that she has not received any databundles for the ****le for the last 2 months as she is unable to use the ****le .On Monday 28 September i went to MTN N1 City Goodwood to sort out this ****le.After the assistant went into my account,she informed me there is 4 gig data available and that i have been getting my free data but that a max of 4 gig (2 gig carried over for 1 month) Next round ,on 1 October i got a bill for the ****le for R8606.50 useage