If you opt to perform this yourself, we'll have to manually unreconcile the transactions. Take note that even small modifications can unbalance your accounts. To minimize the effect of the changes, we can only do it one at a time. Here's how:
Go to Bookkeeping.
Choose Chart of accounts.
Open your bank register, then locate the appropriate transaction.
Select it to expand the view and review the Check column.
Keep clicking the checkbox until it becomes blank.
Hit Save.
Additionally, here are some resources that will help you resolve common reconciliation errors or problems: