Unreconciled a prior period. The history shows it was unreconciled by the register shows checks still cleared. resolution?

Hello,

You can have a transaction in a Cleared (C) status but not be Reconciled (R).  

Cleared just means it was marked manually as cleared or it was downloaded and added or matched from your baking feeds.

Reconciled means you've gone through the reconcile feature and compared the items in QuickBooks to your bank statement and marked it as reconciled and completed the reconcile task.