Cannot create assignment of task &1 to resource &2

What causes this issue?

You cannot create an assignment of the task to the resource because the
status of the task (<LS>Canceled</>, <LS>Completed</>) does not allow
this.

System Response

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

How to fix this error?

Reset the status of the task to <LS>Released </>to create the
assignment.

Procedure for System Administrators

Error message extract from SAP system. Copyright SAP SE.