Debit on a debit not agreed upon

So, yesterday, 14/04/2020 I received an sms saying that my account is in arrears of R1244. I immediately try and contact Telkom to find out what is happening. The balance I was sent is for the current invoice so I am fine with the amount being debited at the end of the month as per our agreement. So, I call but I'm kept on hold because there are only a few agents working and I can imagine it is busy. I drop the call and let it go thinking my account will be debited at the end of the month. For some odd reason I log into my bank account and there I see that they have debited by account for the full amount of R1244. Today is the 15th April and not the 30th. Why on earth will you debit my account in the middle of the month if this is not the agreement?

My account was not in arrears for R1244 but for R361. If this was the amount that was debited I would understand but debiting my account for such a large amount this time of the month is ridiculous. Considering what we're currently going through. How am I suppose to survive the rest of the month?

Very annoyed and ****ed customer.