The reports shows in which templates the created additional fields are associated
select sd.name "Service Catalog Name",
rt.templatename "Template name",
fc.field_name "Fields" from requesttemplate_list rt
left join servicedefinition sd on sd.serviceid = rt.parent_service
left join form_customizer fc on fc.form_name = ('WorkOrder_' + rt.templatename)
where fc.index_tech >= 0 and fc.field_name='udf_sline_901'
order by 1
Go to Admin >> Service Catalog - Additional Fields/Incident - Additional Fields >> Note the API name for the additional field and replace it with the highlighted text in the query