MixItUp Issue - Double Load on Filter

Hello! Whenever I hit the “Lead Pages” button, the elements double load.

To clarify a little bit more, upon hitting the “Lead Pages” button, the page shows the first three elements, and then the rest of the elements slide in from the top.

Does anyone know how to fix this? Thank you!

Here is my test page: https://www.anedot.com/action-pages-gallery-test
Password is “12345”