Data flow &1 is locked by the Change and Transport Organizer

What causes this issue?

InfoObject is locked by another user. Alternatively, the system may be
configured so that the InfoObject cannot be changed.

System Response

InfoObject can be displayed, but it cannot be changed.

How to fix this error?

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

Procedure for System Administrators

Error message extract from SAP system. Copyright SAP SE.