How to reverse duplicate transaction (check)?
If you are unable to void the transaction you can follow the instructions below.
Determine the statement date of the last closed Bank Reconciliation. If the original check date is after that date, you may use use the check date in your reversing transaction. If the check was made prior to that date, you must date the new transaction a day after the last closed Bank Reconciliation statement date.
GL Individual Transaction > New > Use CD (cash disbursement) enter the date and a reference > OK
The original transaction credited cash and debited other accounts. You will debit the cash account and credit the other accounts used in the original transaction.