QB Mac 2014

I'm looking at the Receive Payments screen. I need to apply an existing credit to a customer's invoice. I've clicked the Apply Existing Credit button, I've select the appropriate invoice. My challenge is on the lower left of the screen it wants me to select where the Deposit is to go to. The funds have already been deposited, that's why there's an existing credit. The money's already been deposited into my checking account. If I select that again, then I'm going to get a double entry. What am I supposed to do?