Virtual Card *****, FNB is 'investigating'

I was in the middle of an exam when someone stole R2800 off my virtual card, not sure how that happened. The money was still pending but they said there was nothing they could do other than investigate, this was over 3 weeks ago.. Now on the phone for over 30 min trying to follow up. Do you know Nedbank immediately reversed the funds when it happened to my neighbor?

I thought virtual cards were meant to change the CVV ever minute or so, so how on earth did they manage to get my details..