I'm here to help you sorted your QuickBooks Online (QBO) balance and Bank balance in your account. That way, your books are accurate.
You can start the QB balance on January 1, 2021 bank balance by reconciling the account. That way, the discrepancies will resolve, and you can use the correct balance moving forward.
But before doing that, let me share with you the factors why QBO does not match your actual bank balance. Among of these are:
Outstanding transactions
New transactions for a connected account
Duplicate transactions
Edited or deleted transactions
Credit card (liability) account
Make sure to match and categorize the outstanding transaction before reconciling it. Once confirmed, please follow the steps below on how to resolve these incorrect balances.
Go to the Accounting tab on the left side, then choose Reconcile.
Choose the exact account in the drop-down.
Enter the Ending balance and date.
Click the Web can help you fix it link. This error shows up if there's another user modify the account.
Once everything is cleared, you can now start reconciling the account. You may refer to this article: Reconcile an account.
If you have difficulties with this matter, I'd advise communicating with an accountant. That way, they can guide you with the whole process to ensure your books are correct.
Once done, you can always review the data by opening a Reconciliation Report. Just click the History by the account on the Reconcile page.
I've added some articles about reconciling roadmap, handling various accounts, and other topics.