Output device &1 is locked in the SAP system

What causes this issue?

The output device was locked by system administration.

System Response

The system creates the spool request but as no output request was
created, the document cannot be printed.

How to fix this error?

Please contact the system administrator if you need to print.

Procedure for System Administrators

The system issues an error message and will not allow you to continue with this transaction until the error is resolved.

Error message extract from SAP system. Copyright SAP SE.