Not sure what happened here....

So my cycle works like clockwork. I have a 5 day period and my cycle is 31 days in length. My expected AF was a week off for august, so I adjusted when AF arrived. Up until this morning, my fertile window was 8/9-13/9 and I was 8dpo (9 this am) expected AF 9/30. Now my expected AF date is a WAY off 4/10, and its telling me I'm 3dpo?? I know based on symptoms I Od btwn CD12 or CD13 and for sure I will start 29/9...so why does glow continue to get it wrong? Tg I'm tempting and recognize symptoms of O or I'd have ZERO chance of pregnancy