You can redo your reconciliation in July so that you'll have a new and correct report. The old one will be kept in your records though but with all the changes you make.
Another thing is that if you've already reconciled after July, you will want to undo them first because the starting balances will change after you'll do a correction.
Undoing a reconciliation can be done by removing the R mark of the transactions in a particular period in the register. Therefore, if you also need to undo multiple transactions months after July, I suggest letting an accountant user do it. Their QuickBooks version has a tool to unreconcile transactions in batches.
Select Accounting.
Select the Chart of accounts tab.
Find the account that has the reconciled transaction. Then select View register.
Find the transaction. If the transaction is reconciled, you’ll see an “R” in the checkmark ✔ column.
Select the transaction to expand the view.
In the checkmark ✔ column, select the box with the “R” until the box is blank, and confirm if you're prompted. This removes the transaction from the reconciliation.