Having had a 5/3 account before, I know how much they like to jump the gun on overdraft fees. I've received one where I'd dump the money in the morning, write a check a couple hours later. Then the check clears later that day and some how get an overdraft fee, even though money to cover it was deposited.
OP, call their CS line. If this isn't your first dispute over an overdraft fee, prepare for a fight. It has something to do with the way the bank you opened the account at processes transactions(in my case, they process the purchases/withdrawals before the deposits). If the CS line doesn't help, you'll then have to take it up with the bank you opened the account at.
Thankfully after the 3rd time, I closed the account and opened an account at a local bank. Look online for feedback on them and you'll see that Fifth Third likes to go crazy on the overdraft fees, even when there shouldn't be any.
[quote name='gokou36'] Are you 100% sure that they're not tacking on more fees because you didn't pay it off?[/quote]
If it is just one transaction saying "overdraft fee", then yeah, it is just one fee. OP, is that what it is saying.