Block slider mobile second image does not load

I have a problem with my slider block on my site. I couldn’t find any info about it online and tried a lot of things. The problem is that the second image of the slider doesn’t load if you go on the site on mobile. If you reload the page on your phone, the second image eventually does load.
How can I make it so it loads from the first time entering the site?

The page I need help with: [log in to see the link]