This may be because of a few stale permissions in the project in which you are trying to create the template.
You can resolve this by identifying and deleting the stale records using this SQL.
select role_id from role_operation ro left outer join ia_project_association ia on (ro.resource_value = ia.id) where ia.id is null and resource_value like '%prpl%' ;
select role_id from operation_cluster ro left outer join ia_project_association ia on (ro.resource_value = ia.id) where ia.id is null and resource_value like '%prpl%' ;