Follow below steps.
1) Open HR case form and under 'Comments and work notes' section click on filter icon. and click on 'Configure available fields'.
2) If 3 fields already not available then bring to selected slushbucket and save it.
Follow below steps.
1) Open HR case form and under 'Comments and work notes' section click on filter icon. and click on 'Configure available fields'.
2) If 3 fields already not available then bring to selected slushbucket and save it.