Since the wrong amount is posted in your actual bank, we need to reflect that amount in your bank register. So when you deposit the 4 checks, you’ll add another line to account the $20 excess. That way, you can match the downloaded transaction to it.
On the other hand, if you’re not sure how to account the excess amount, please consult an accountant. In the meantime, you can assign a temporary income account and edit it later on.
Please get back to us here if you have other questions.
Other Current Asset = if the Deposit from banking is less than you know you made. That's done using Make Deposit, select the 4 checks you need to process from Undeposited Funds, and then bottom, enter "cash goes back to" and Other Current Asset account. Now you have a lower Net deposit. When you get the refund from the bank, you enter this as the manual Addition line, as "from" Other Current Asset, in the Deposit when the bank returns the funds.
If the Deposit entry in QB is too High and the bank processed it as such, then the entry in QB has the additional line as @JessT shows, to Other Current Liability. It is not "ask my accountant" which is on the P&L. It is Liability = not our funds to keep. Then, when the bank shows they removed that extra amount, you will use Write Check and "pay out" the Other Current Liability.