CMS Collection not displaying properly

Design help CMS
1

Hi, my CMS collection seems to leave a couple of blank boxes, any idea why? When I change to 2 columns it sits fine, but anything more, adds these 2 empty spaces.

Here’s a screenshot:

image
image1070×815 70.3 KB

Any advice is much appreciated.

Thanks,
Tark

Here is my public share link: (Projects)