i don't have accountant firm tab on mange users section. i am using QuickBooks Plus

Welcome aboard to the Community, @Ravindu2012. I’m here to give you insights about the Accounting Firms tab and ensure you can undo the banking reconciliation in QuickBooks Online (QBO).

I’d like to know which country you’re using QuickBooks for. Depending on the region in which you signed up with us, the Accounting Firms page may not be available for you to invite an accountant.

QuickBooks for the United States, United Kingdom, Australia, Brazil, Canada, France, India, Mexico, Singapore, South Africa, and other countries are supported. If you’re using one of the aforementioned products and unable to locate the Accounting Firm tab, let’s access your account using an incognito or private window. This is ideal for diagnosing browser issues because they prevent cookies from being saved on your system.

Here are the following keyboard shortcuts for quick navigation:

• Google Chrome: Ctrl + Shift + N
• Safari 11 or newer: ⌘ + Shift + N
• Mozilla Firefox: Ctrl + Shift + P
• Microsoft Edge: Ctrl + Shift + P

Once logged in, check out your Manage Users window. If you’re able to view the Accounting Firm tab, you’ll need to clear your browser’s cache. This helps the browser to function efficiently. You can also switch to other supported browsers as an alternative.

You’re right, only accountant users can undo an entire reconciliation. To proceed, you’ll need to invite your accountant to your company. Please know that you can go to the Accounting firms section or the Company admin (select This user is my accountant) for users that don't have the Accounting firms option.

For accounts that doesn't have this option, you can follow the steps below to add your accountant:

1. Click the Cogwheel ⚙️ icon then choose Manage Users.
2. Tap the Add User button and select Company admin.
3. Mark the box for This user is my accountant.
4. Press Next and enter the accountant's information before hitting Save.

Once the accountant is added, he will receive an email with a link to sign into your QBO company. Here is an article with the complete details about this process: Managing accountant users in QuickBooks Online

The option to invite an accounting firm will not be available in all QuickBooks locations. You will need to manually amend a specific transaction from the completed reconciliation in this situation. I'm adding this article as your reference: Undo or remove transactions from reconciliations in QuickBooks Online.

When you're ready to reconcile your entries again, use this link as your guide: Learn the reconciliation workflow in QuickBooks.

If you have any other questions about managing your account, please feel free to leave a comment below. I'll get back here as soon as I can to help you again. Thanks for dropping by, wishing you a good one!