For those missing a fertile window

I've been reading about ladies not being able to see their fertile windows highlighted in green on the calendar. I screwed up my calendar a few minutes ago by changing my status and it erased all my period information. Luckily, I could still see the dates highlighted in pink, though it wasn't registering that I'd entered cycle information at all, giving me "N/A" where it used to tell me the cycle day (that seems to be an app glitch). If you go back into your calendar, re-adjust your last period date and save, it should bring back your fertile window in green. Let me know if this works for anyone, or doesn't work.