Total disgusting service from Nedbank

The way Nedbank has treated me today is absolutely revolting, disgusting and Incimpitent, since this morning 8 am up until now 14h27 my issue has not been resolved, 6 agents later and no one could assist and resolved, last 3 agenrs whos names i actually took down, Leon, Melony and Rowan. My issue is my credit card payment, in the beginning of this month a debit order went off from my current account for the amount of R 300 which was rightfully authorised by me via my banking App, today i woke up with an sms from Nedbank that an amount of R 350 was debited from my current account towards payment to my credit card, this has left my current account with a - R 350 owing on my current account, i never authorised a debit order to go off in the middle of a month because salary date is last day of the month. I called Nedbank and one agent actually got as far as seeing that i did not authorise such a debit order, but also he could not trace who actually did so. I defnitly did not. A few days ago i transferred an amount of R 235 from my current account to my credit card, weeks before this it was R 2500 that i paid to my credit card, and 1 October i paid R 10 000 into my credit card, i have since i received my credit card continuously paid more than the expected amounts i was supposed to pay, not once in arrears, always up to date. My concern is, my current account is in a minus state, and this debit order is going to be returned unpaid, and i am going to be listed as a bad payer, my credit score will drop and my credit worthyness and future credit limit increase to my credit card will be affected because of this, this is disgusting and totally not accepted, as i am not to blame for this, which actually brings me to another point, a month ago i was informed by a consultant that i can qualify for an automatic credit limit increase by end November / December this year, seeing that i am a platinum credit card holder, and my payments are well managed, which it is, but a few days ago i queried this again and i was informed that unfortunatly that is not so and i cant qualify, how misleading can this be to me as a dedicated customer who pays and looks after my credit card payments regularly, which can obviously be seen on my payment history, this is so disgusting, and a slap in my face. I was excited to think i would have some extra cash for Christmas. Seems not even though my credit card has alqays been paid and up to date, another slap in the face. And yet Nedbank wont assist. I am so dissapointed in the way i am being treated !!