Marking missed pill

I entered that I have been on the pill for two years (which is true), but there are same days recently i missed the pill. How can I mark that on the calendar/<a href="https://play.google.com/store/apps/details?id=com.glow.android.eve">period tracker</a> thing? I have PCOS and irregular periods when I'm not on the pill, so marking when I take/don't take the pill will affect when my period is.