Overmixed pate sucree
Solution 1:
Use it as poundcake batter.
Judging by the photo, it looks a lot like perfect cake batter.

Solution 2:
Chill it well, work in the missing 80g flour, chill again.
Use as planned, accept that the pie crust might be a bit tougher than expected. Adding a pinch or two of baking powder to the flour can counteract it a bit.