I remember reading an article from Australia where a woman requested to withdraw a five figure sum (over 20k) in cash from her own bank account but they're like "sorry, we can't do that" making excuses on the way of "need proof on how you acquired such money", even though she provided all the evidence, they still refused anyway. She was like "WTF? It's my own money!" so there's a possibility that banks dictate how much one can withdraw.