Money went missing without any notification.

Money went missing out of my account cause of "technical issues" on March 23. Which I've never heard in my life of. HTF does a bank lose your money where you have no access to it?! But we are supposed to trust banks with our money... I had to buy something today but now I can't cause I'm waiting for them to resolve their technical issue. Where the turn around time can't be verified! I'm getting paid tomorrow and have no clue whether I'll have my money in my account or if that will get missing too. How am I supposed to trust FNB if something like this can happen on my account?