I’m confused

So I’ve been using this glow app for a while now to track my period and ovulation , but something felt off because me and my husband have been trying to get pregnant for a while now so I went into another ovulation and and period app and put the first day of my last period into the calendar. On the Femia app my fertile window is already half way over with and the ovulation day is the 2nd of December but my glow app is saying my fertile window didn’t start until today. I don’t know which one to believe. I put the same day for the first day of my last period on both of the calendars and even triple checked to make sure it was right.