How can I undo a bank reconciliation for a specific month?

Hello there, @lhuichoo.

Thank you for reaching out to us here on the Community page. I can guide you on how to undo the previous reconciliation in QuickBooks Online.

The Undo option for a reconciled period is only available in QuickBooks Online Accountant. If you don't have an accountant user on your account, I'd suggest inviting one.

1. Go to the Gear icon, then select Manage Users under Your Company.
2. Click on Accounting firms, and tap Invite.
3. Enter the information.
4. Click Save.

Once done, let your accountant undo the reconciliation for you. 

Otherwise, you can undo the reconciled entries one at a time without the help of an accountant. You can use this article as your reference: Undo and remove transactions from reconciliations in QuickBooks Online.

As you continue working with QuickBooks and managing your bank transactions, you can as well open the topics from our help articles as additional resources in the future.

Feel free to add a comment below if you have any other questions. I'm more than happy to help. Have a good day!