Banks sure seem to make errors that favor them a lot, especially with fees, but has anyone ever had a situation where a bank made an error in your favor? Not something silly like a teller giving you a $5 bill instead of a $1 by mistake, but nice things, like a bonus received being more than it was supposed to be, or maybe incorrect reporting that wound up saving you a bunch of money, or your balance suddenly increasing for no reason at all one day, or maybe the interest rate applied to your CD was a higher rate than it was supposed to be, or a purchase you put on your credit card never actually showed up and you never got billed for it... or other such "nice" kind of errors in your favor?
For all the "Oh, I'm sorry, yeah, that fee was a mistake, gee, glad you, uh, noticed it" from banks, does it ever happen the other way around for people?