RiverPark Playground - Main entrance -Dogs Park

I would like to make a complaint about the customer service I received. I was treated very disrespectfully when I asked to wash my hands in the restroom. The employee told me the restroom was for employees only and refused to let me use it, even after I explained that I only needed to wash my hands. I understand there may be policies, but the way I was spoken to was rude and unprofessional. If the restroom is only for employees, there should be a clear sign. I believe customers should be treated with more respect.