Let me show you how you can delete or undo your last reconciliation within QuickBooks Online,staggsfamily98.
Deleting transactions from a reconciled period could impact the starting and ending balances of past and future reconciliations. It's advisable to consult with an accountant to determine the most appropriate method for removing previous bank reconciliations.
Go to the Transaction menu and select Chart of Accounts.
Choose the appropriate account and click View register.
Look for the reconciled transactions and click.
Then, Delete.
Note: Since the transaction you are deleting has been reconciled, it could put you out of balance the next time you try to reconcile.
Moving forward, if you're only trying to undo reconciled transactions, I suggest inviting your accountant to your company so they can manage the deletion or reversal of previous bank reconciliations at once.
From the Accounting menu, select Chart of Accounts.
Locate the correct account for the transaction and select View Register on the Action column.
Select the transaction to edit.
In the reconcile status column (indicated by a checkmark), repeatedly click the top line of the transaction to change the status as blank to indicate that it's not cleared or reconciled.