1. Go to the room that you entered Cash as payment by mistake

2. Click Cash Register showed on the picture.

1. Enter negative amount that you want to take out the cash (-49.99) and select Cash as payment type.

2. Enter positive amount (49.99) and select Credit Card as payment type. So the new balance will show "0".

3. Hit Continue to process the credit card.

Picture shows $10 which can be any number that you enter wrong.