I used to bank with Key Bank. One day when contracting I had a bunch of transactions hit my personal account, and so I deposited funds (cash) to cover it. By a wallclock ordering, my account never was out of the black...

... until midnight that night, when Key Bank "reordered my transactions" and said that electronic transactions were considered to hit my account at midnight, regardless of when they actually hit (like using a keypad at a store)., i.e. you could have $200 in your bank at midnight, deposit $300 cash at an ATM at 9am (balance $500), and at 5pm buy $300 of groceries, leaving your balance of $200. All good, right? No, in Key Bank (and other's) policy, you had $200 at midnight, then a $300 transaction for groceries, overdrawing you by $100, assessing you a $35 overdraft fee, and then you clear the overdraft at 9am, leaving your balance of $165.

The way this worked out for me was $280 in overdraft fees for a single day where I was never actually in the black until they ran their shady game.

They waived one fee as a "courtesy". I refused to pay the fees. My account was closed.

They then reported me to ChexSystems as a high risk and delinquent customer and for the next few years I couldn't open a bank account at any bank that used ChexSystems (the very vast majority). Even when the whole transaction reordering thing was made illegal, even when there was a class action against Key Bank, etc., of course, they admitted no wrongdoing, so didn't remove the black mark against me.

Because you've tripped an AML flag you unbearable dweebs, this happens a thousand times every week and the story is always the same, tipping off rules actively prevent notification. But of course the reason must be political, because that's the only story that will drive traffic to an otherwise unknown outlet