Total disappointment

I have been with Telkom since 2022, using their cellphone contract... I didn't have any problems up until this couple of months... -I will pay the phone at Pep but it will get closed and the demand a late payment fee. -the phone will be opened for couple of days then they suspend their service "due to no payment" even if I payed. -last month I went to their store I found out that I need to the last R2200 before my contract ends, so I payed R1200, knowing that I only have to pay R1000 this month to my surprise the invoice comes back that I owe them R1986. 00