Nedbank ATM restarting itself while withdrawing!!!!

I am extremely disappointed with Nedbank's cardless withdrawal feature. While I was withdrawing money today, the ATM suddenly restarted. I waited until it booted up, but unfortunately, I did not receive my money. When I called the service desk, I was told the amount I was trying to withdraw was showing as having been cashed out. How can we trust the bank with our money if we are going to encounter such silly incidents?