How to enter a check in a closed period
A check cannot be entered in a closed period. The period would need to be reopened to enter a check through the usual process of creating a bill then printing a check. However, a check could be recorded through a journal entry. Using a journal entry to record a check in a closed period would allow you to reconcile your bank account but the check would not show in the check register.
To populate the Bank Reconciliation, the journal entry must credit the bank account and debit an offsetting account such as expense.