How to remove a Credit Memo or the remaining balance
If you have created a Credit Memo in error, either as a duplicate or for any other reason, and you now want to remove it, follow these steps:
First, if your login profile has Administrator privileges and the Credit Memo date is in the current accounting period, you may delete the Credit Memo by clicking the delete button at the bottom.
If the Credit Memo is dated prior to the current accounting period, you may create a negative credit memo.
Together, both Credit Memos will wash each other out.