No operations available for selection in chosen maintenance task list & &

What causes this issue?

You have selected a <DS:GLOS.maintenance_task_list>task list</> to
include in the <DS:GLOS.maintenance_order>maintenance order</> or
<DS:GLOS.service_order>service order</>.
The system can no longer provide operations for you to select from for
this task list because they have all already been included in the order
and the indicator <DS:DE.ONE_OPR>One-time operation selection</> has
been set.

System Response

INCLUDE KEINE-VERARBEITUNG OBJECT DOKU ID TX LANGUAGE EN

How to fix this error?

Remove the indicator <zh>One-time operation selection</>.
<zv>WARNING! The long text for this message is also displayed for the
messages IW614 and IW615 (INCLUDE)</>

Error message extract from SAP system. Copyright SAP SE.