The Image gallery keeps adding spaces

 Hi, I have the showtime gallery running on the latest version of Joomla, 3.9.20, I am also using the Yootheme 2.0 templates.
I have created galleries using the Joomla custom fields and have it showing on the page, Also on the page, I have RSform running, so when I open a form and fill out the details, the thumbnails images in the wall in showtime gallery keep spacing themselves out vertically to the space of the thumbnail.

I can not figure out why, can someone have a look to sort this out, please?
you can see the issue here: https://switchautos.co.uk/hatchbacks/switch-autos-vehicle-08

HI, Sorry
I removed the gallery as it was jumping all over the place and was causing conflicts

ok, will do as I really like how it all works in the back end but the front end is where the problem is, I will set up a test page today so you can see