Nanny being exploited by agency

I recently spoke to a lovely Filipino lady who is employed by an agency here. She works five days a week with a family and then on the weekends the lady who runs the agency has her working for her at her home. She does not pay any health insurance for this lady. My question is, who can we report this agency to? Also, is there any point in reporting her as she and, I’m assuming, other agencies operate here in the knowledge that they won’t be inspected by anyone. I’m sure there are many individuals also exploiting nannies and I hate to think that we are living in a country that will turn a blind eye to this modern-day slavery.

Read Auntie’s answer and comment on CNS Local Life