Hello Chaz B!
You can undo the reconciliation. Let me show you.
When you undo a reconciliation, your beginning balance reverts to the beginning balance of your previous reconciliation. Also, all transactions on that reconciliation become uncleared. Then, you can re-reconcile them again. Go to the Banking menu, then select Reconcile. On the pop-up, click Undo Last Reconciliation.
Another option I can suggest is to restore the company file if you created a backup. From there, you can start a new reconciliation from scratch.
You can check this link: Reconcile an account in QuickBooks Desktop. This will explain how to reconcile and how to fix issues when reconciling.
Leave a comment below if you have other concerns with your accounts. I'll be here!