Glow changed my cycle!

My cycle is regular, 28 days give or take a day... but for some reason Glow put that I should be getting my period *34 days* after my last period. I don’t get how it calculated that. Also, my ovulation date keeps changing. I’m just so confused, I don’t know if I’ve ovulated already or I’m still yet too. All my OPKs have been negative. Ugh, I really thought this month would be our month 😔. Has this happened to anyone else? Does anyone know why this could’ve happened?