Trumped up Fees

So Telkom is charging me R202.70 for a Payment rejection fee for the 26th Aug (Sunday). Telkom got their money on Tuesday (28th August) and there is no evidence of their attempt to debit my account on my bank statement.

I chatted with Pinky online regarding the above. She then told me that it MAY have been my bank who rejected the debit order before it reached my account. IT MAY!!!! I asked for a rejection code and description (I work in the industry) and was told that they don't have that information on their side and the debits are handled by a different department. I asked her why they are attempting to debit on a Sunday, a non business day and our chat was promptly ended by Pinky. I am 2 months away from this contract ending and I don't mind been listed by Telkom, you are not getting my money on the 25th September.