Validation occurs for data that has been entered into the fields for BC, Sph, Cyl, Axis, Diam, Add, and Add Des. This validation process will ensure the Rx is available for the product associated to the Contact Lens Rx. Rx validation is checked on the right eye and then the left eye. If an invalid parameter is found, an error displays and indicates which eye has the error. If the message indicates the right eye has an error, we recommend you verify the data for the left eye as you make changes to the right eye.