Can't change my cycle length

Anna • Baby #1. BFP 8/12/15. it's a girl: 10/28/15. Due 4/21. Born 4/10/16! 🎀 Baby #2: Due 2/2/18. It's a girl: 10/4/17.
Hi, I originally put in my cycle length as 26 days by mistake. Now I have changed the cycle length to 28 days in the health profile, but the Glow calendar still shows that my next period will start in 26 days, and my fertile days are way off because of it. Is there a way to fix it ? Thnx