Unacceptable billing for loyal client

This is cathrine Honoko secondary under my sons account a loya client of telkom for the past +-8 year,i recently change my plan in may 2018,taking plan that amounts to 559.00 pm which icludes telkom line , uncapped data and free modem ,how ever the first month i was billed seperate for the "free moderm" R880.00 total being 1800.00 ,i laid a dispute in june they claimed to have rectified the bill,I have been paying 900 monthly however on the 20 october they closed my internet line ,i called to enquire they claimed to not have receive a payment in june ,only now in october they close the line ,they sent me stament dated 9 august but the bill has call charges for may, june, july and august yet i have been paying every month,i am very very ****ed off,as i need the internet service and its very unacceptable to pay yet be their statement shows balance brought forward for 9 july .no one can explain where that amount comes from .if i did not pay e1 august why did they not close the line then.they only close the line 20 october .my kids are unable to do school project yet i pay for a bill .ever since i changed my plan im receiving the worst service ever ,their accounts department is ridiculous ,im even looking at other plan with other internent providers for better service .i need good value for money ...