Telkom Acc no ***

Telkom did it again. I am so disappointed in Telkom billing me again with extra cost of R202 for a debit that did not go through. I did not once missed an instalment If my debit did not go through I go make a payment cash. My account is up to date but they put their extra cost of R202. My account number Telkom ***. This time they going to far they suspended my line. Is this even legal