How do I add I didn't have my period on a period day according to the app?

Krystal
According to this app, it says today 1/16 is suppose to be the start of my period. But I have yet to get it. So how do I add to the app to let it know no blood flow or missed period? Without changing my period days on the calendar 

Glow Resources

Let’s Glow

Glow is here for you on your path to pregnancy

Glow helps you navigate your fertility journey with smart tools, personalized insights, and guidance from medical experts who understand what matters most.

25+ million

Users

4.8 stars

200k+ app ratings

20+

Medical advisors