Do you balance your checkbook/reconcile your account?
Yes, over the years I have found errors. One time I had an account that required a minimum balance in order to avoid paying fees. My deposit would drop into the account and I would wait a week or two before I paid any bills from it--never going below the minimum. So, I was really surprised to see the fee. I challenged the bank representative to tell me which day did the balance go below. The bank rep couldn't (because it hadn't), but had to "research" it. 2 weeks later, I hadn't heard back so I then talked to the manager who immediately fixed it. (I no longer have that account).

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