I am using QB online.  This issue only occurs with one bank account.  The other account reconciliations are working properly.  The filtering appears to be set correctly.  The browser is irrelevant.  I cleared the cache.  Once again, the register shows all transactions and appear and are noted with a "R".  I switch to Reconcile and all of the activity for the proper period end disappears and the out of balance amount is equal to the sum of the activity for the period.