You don't need to re-upload the 2023 and 2024 transactions, rkoorapati. I'll shed some light on how you can clear out these discrepancies so you have accuracy in your books moving forward.

You'll need to contact your bank first to obtain a copy of your bank statements. Since verifying the accuracy of your unreconciled transactions will be challenging without bank statements.

Once you have it, review each unreconciled transaction to ensure its accuracy against the statements. After that, proceed with reconciliation. If you entered an opening balance transaction when reconciling your January 2023 entries, you will need to delete it. Then, undo all reconciled transactions from 2023 and 2024. Note that you can only do this one transaction at a time.

With this, I recommend contacting your accountant. They can use QuickBooks Online Accountant to undo the entire period simultaneously. However, if you prefer to handle this process yourself, follow the outlined steps below:

1. Navigate to the Transactions menu. Then select Chart of Accounts.
2. Find the account and choose View register. 
3. Filter the register to include only the relevant transactions.
4. Review the check column. If the transaction is reconciled, you’ll see an - R.
   
   
5. Choose the box and keep clicking it until it's blank. It removes the transaction from the reconciliation.
6. Once done, hit Save.

After completing these adjustments, you can proceed with reconciling transactions from before 2023 up to 2024.

Regarding your question about downloading all data from QuickBooks Online (QBO) and uploading only the data for 2023 and 2024, this option isn't available. However, if entries before 2023 were uploaded to the Banking page, you can undo them to remove them from your records, leaving you with only the data from 2023 and 2024.

Moreover, to address your additional inquiry, it's possible to create a new QBO account, reconcile it for both years and cancel your existing account to reduce subscription costs. You can follow Chrea's recommendation or directly purchase a new QBO account and transfer your data from the existing one to the new one.

If you have the Advanced version, you can make a copy of your QBO Advanced company to start a new one, simplifying the data transfer process. For Simple Start, Essentials, or Plus versions, you'll need to export data from your old file to the new company.

Alternatively, you may look for third-party migration tools in the QuickBooks App Store to assist with the transfer, especially if you have a large volume of data. Using a third-party service to migrate data to a new QBO account can be efficient, especially for complex data sets. However, no migration is entirely error-free, so a thorough review is necessary after migration to correct any issues like missing transactions or discrepancies and ensure data accuracy and integrity.

Once the new account is configured, reconcile transactions for both years by comparing QuickBooks records with bank statements. After reconciliation, you can cancel your existing QBO subscription to reduce costs.

Finally, I've compiled a few resources you can refer to learn more about managing your reconciliations:

• How do I view, print, or export a reconciliation report?
• How to view details for missing reconciliation reports or reconciled transactions in QuickBooks Onli...

Come and visit us if you have further questions about reconciling your bank accounts. The Community and I will be here to lend a helping hand.