Grid not displaying properly on mobile

Hi,
I’m having trouble with a grid not displaying as intended on mobile, as in it doesn’t stack.

I’ve read in other posts to set the columns to 1, and I’ve done that, but it still doesn’t stack.

It’s the " Unsere Qualifikationen" grid on the “Über uns” page.

Thanks so much for any help with this!

Here is my site Read-Only: Webflow - MVP