How to open previous reconciliation with wrong date

Hello there. 

I'm here to assist you with your reconciliation concerns.

To open a previous reconciliation with the wrong date in QuickBooks Online (QBO) International, you'll need to manually undo the reconciliation for that specific period. Here are the steps to follow:

1. Click the Gear icon at the top and select the Chart of Accounts.
2. Locate the appropriate account for the transaction and select View Register on the Action column.
3. Identify the transaction to edit.
4. In the reconcile status column, repeatedly click the top line of the transaction to change the status. 
5. Then, click Save.

• C - Cleared.
• R - Reconciled.
• Blank - Not cleared or reconciled.

The Undo option for a reconciled period is only available in QuickBooks Online Accountant. I'd recommend contacting your accountant and letting them undo the reconciliation period at once.

See this article for more details: How to Unreconcile a Transaction or Undo a Reconciliation. 

I'm adding this reference that'll guide you anytime you need help while doing or fixing reconciliation: The reconcile workflow. 

I'm always available if you need clarification about reconciliation. The Community is always available 24/7 to assist you.