Hi, I have 2 questions: Can you delete a bank reconciliation and re do it? Can you delete a tax return and correct errors?

Hi there, @noeleenmulcahy. It's good to see you posting in the Community space.

To answer your first question, yes you can in which the Undo option for a reconciled period is only available in QuickBooks Online Accountant (QBOA). To undo them in batch, you'll want to let your accountant do it. Give them this article for a guide: Undo and remove transactions from reconciliations in QuickBooks Online.

Once done, start doing the reconciliation process again. I recommend, comparing your bank statement with what was recorded in your QuickBooks Online account. 

For a complete guide in reconciling transactions, see these helpful resources:

• Reconcile an account in QuickBooks Online
• Learn the reconcile workflow in QuickBooks

As for your other question, you can delete a tax payment, to record it with the correct amount. 

Here's what you'll need to do:

1. On the left menu, click Taxes.
2. Go to the Taxes tab.
3. Under Sales Tax, choose Payments.
4. Select the payment.
5. Tap the drop-down arrow beside the View hyperlink.
6. Choose Delete.
7. Hit Yes on the confirmation screen.

Once done, record the correct amount. 

Get back to me here if you have other questions in QuickBooks. I'm more than happy to offer further assistance. Have a great day.