I'd be glad to walk you through editing your account's opening balance, useranamika-b.
The opening balance is the starting point for the account that summarises all past transactions in your up to the opening balance date. When you enter a balance the first time you create an account, a deposit will be posted in your register affecting the Open Balance Equity. It should also be the only entry that's already reconciled.
You can update it by editing the deposit. Let me show you how:
Go to the Accounting menu and select Chart of Accounts.
Look for the account and View register.
To easily locate the deposit, you can use the filter option above the DATE column.
Select the Deposit for Opening Balance Equity and then Edit.
Update the Amount and click Save and close.
Select Yes to confirm and Yes again to allow the system of the modification.
If the reconciled status was removed after editing, you can put it back reconciled by repeatedly clicking on the reconciliation status until you see the R (reconciled) mark.