Slider arrows no longer working

Hello,

In the Lightning theme, I’m using the “Lightning Homepage Slide Show”. I have 5 images which work fine in automatic. But the manual mode is “broken”. Clicking on the left or right arrows on the slide show images does not display the next or previous images. Instead, it just scrolls the whole page down a few inches.

Could not find any info on forums.

Thanks for your help.

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