First National Bank
Outstanding debit card authorisation

I received an sms to say that my cheque account balance is less than R250 and to deposit money to avoid outstanding fees. I was confused because it shouldn't be less than R250 so I logged on and to check things and according to my online cheque balance it is well above this amount. I also noticed that there is a whopping R676.19 outstanding debit card authorisation!
Can someone please explain to me, firstly, why I get communication saying one thing but my online information differs? And, secondly, what this outstanding debit card authorisation is all about? I receive sms's after each swipe, there shouldn't be anothing outstanding at this point.
I find this very concerning.

Company: First National Bank
Country: South Africa
City: Seapoint

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