You have to reach out to your bank to retrieve your old bank statements. However, if your bank is connected to QuickBooks, you can check your register in QuickBooks Online to see the transactions added on your account.
Click on Accounting at the left pane, then select Chart of Accounts.
Look for the account from the result, then click on Viewregister under Action.
Scroll up/down under the Bank Register to check for the transactions.
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