Image not going to full width of container

I posted this question two days ago and it appears to have disappeared.

We installed gallery bank on this url https://wptest.wgaaen.com/studio-a/ and the images were done to fit the box width and height, but they are appearing smaller, not going to the full width of the container.

We’ve looked in the css, went through the settings, tried making the images bigger than the container, and nothing works.

How can we fix this?

https://www.ads-software.com/extend/plugins/gallery-bank/