Upper left tab for gauge not working

I tried customizing caffeine sensitivity by clicking upper left hand corner gauge and then by clicking my self described level of caffeine sensitivity. Clicking upper left brings up next window, but then clicking the "highly sensitive" tab does NOT WORK - nothing happens. And your app is also not allowing me to click male or female - again nothing happens. iPhone 6s Plus IOS 9.2.1

First time google cal user about UP Coffee