Telkom

Telkom debited from my bank account on December 31, 2023, and there was a balance left afterwards. They credited the amount taken on January 2, 2024, saying that they had not received the money. What confuses me is how the hell they debited, and my statement shows a balance after they debited, but they did not receive! On January 15, 2024, they have the nerve to debit R634.99 from my account for not receiving their R317. If my agreement with them is to debit at the end of the month, where do they think I get the money on the 15th?