Standard Bank ATM fault

I went to a Standard Bank ATM at Engen Pitstop in Ermelo. I requested a withdrawal of R3000. The ATM didn't dispense the money and gave a slip that says technical error. I received an sms that said money was withdrawn. When I went to the Bank a few moments ago, they tell me they need to investigate and will refund me in 11 days?

Why must I wait 11 days when their ATM machine is at fault not me? I must suffer for 11 days because of Standard Banks fault?

Is that what Standard Bank wants of us. They make a mistake then clients suffer??