An individual shall not fit and adjust contact lenses, including plano contact lenses unless either of the following applies:
(a) The individual is a duly registered contact lens dispenser as provided in Section 2561.
(b) The individual is an unregistered individual who performs the fitting and adjusting under the direct responsibility and supervision of a duly registered contact lens dispenser who is then physically present on the registered premises. In no event shall a registered contact lens dispenser supervise more than three unregistered individuals.