Telkom double charge every month

Hi, Telkom keeps forgetting to debit me on the date I've sign the contract, I end up having to pay double the following month. They do it every second month when they forget to debit or there was technical issue. It's financially frustrating at times you don't realize they didn't debit you and end up with no service to your network and having to pay double the amount when you call them all they tell you is it was a technical issue they never are sincere to their customers cause they use call centre agents to follow protocols and that's that's sick of telkom