This app has the wrong weeks and days

Ria β€’ Married 1 year ❀ 1st baby due May 2019 πŸ’

Hello,

My baby is due June 2nd. I am currently 8 weeks today. But because my last period was on Aug. 21st the weeks and dates are off on here saying I am 8 weeks 6 days. Does anyone know how to correct this?

Thanks best wishes!