Ok got the issue now, please check the working code, Mark my answer as correct after validation. Please note there is OOB script which is making this change when on hold reason is not Awaiting caller hence you need script only for this condition ok.
Script :
(function executeRule(current, previous /*null when async*/) {
// Add your code here
gs.addInfoMessage("Working fine");
var incident = new GlideRecord('incident');
incident.addQuery('parent_incident', current.sys_id);
// incident.addQuery('state', '3');
// incident.addQuery('hold_reason', '1');
incident.query();
while(incident.next()){
gs.addInfoMessage("Working fine fine");
incident.state = current.state;
incident.hold_reason = current.hold_reason;
incident.update();
}
})(current, previous);
Condition:
