Late period button?

Km • 27. Married 5 years. Our daughter Stella Claire is our entire world. Born Nov 15. 2015. Pregnant with #2 due in April.
I'm sure this has been explained a few times but I can't find the period late button. When I click on my <a href="https://play.google.com/store/apps/details?id=com.glow.android.eve">period calendar</a> it lets me move it, save it or say it was today. I'm due today but it's late. Anyone know where I can input that?