App Changed Ovulation Date to a Week Later


So last week I was ovulating and I could tell from my cervical mucus. We are in our 4th month of trying and I decided that this month I would also check my basal temperature. For the most part that has been going fine except for this morning when I took it and my temp for the last 3 days was a little high, the app changed my predicted day of ovulation to 2 days ago instead of the previous week. I hope that it won't mess up my predictions in the future. Has anyone else had this issue before.