Telkom mobile contract debit

I’m really really disappointed on Telkom, they have added payment rejection fee on my account for the second time meanwhile they are the ones who never debit the account on the agreed date, I always have to pay their contract personally and I can assure you that their monthly amount of R300 is always available on my account for them to debit but they never debit then I end up paying it directly. I fail to understand where’s this rejection payment fee coming from? Talk about **************** ???