I have set up the Ink Appointment on a Divi Elegant Themes template. On a desktop and Android tablet it works fine but on an iPhone it won't allow me to pick an appointment date. After I select a service and click on the date field, all that opens up is the keyboard for typing. Since I don't get the popup calendar I can't set an appointment. What do I need to do differently to get the calendar to popup so I can set an appointment on my cell phone?