perpendicular cross sectional area along centerline

Hello,

I am trying to measure cross-sectional area of slices perpendicular to the centreline of a tendon that I segmented. When I go to the cross-section analysis module, all the sections are blank and I can’t see any details about the area or other measures. I will include a picture below. How can I fix this problem?
Screen Shot 2021-06-24 at 11.16.37 AM