Please select variation message disappears

Hi,

When I load the page on a product the “please select variation” message pops up for a split second and then disappears. Why does it not stay up so people know they need to select a variation to get shipping costs? https://www.loom.com/share/59704f5f793c4497ad0d444cee0eca44

Thanks,
Vanessa

The page I need help with: [log in to see the link]