Uncaught TypeError: Cannot read properties of undefined (reading 'clientLeft') on WordPress

[sveloo]

Hey guys,

I've been using Swiper really great for heaps of WordPress sites but I've come up with this error on one of the new projects I'm working on. Can't seem to figure out why! Anyone else have this?

The Swiper is initializing fine and all good... but it just doesn't advance or move or fade. I checked the console and this came up:

Uncaught TypeError: Cannot read properties of undefined (reading 'clientLeft')
    at H.slideNext (slideNext.js:15:47)
    at autoplay.js:56:33

Any help would be greatly appreciated!

Thanks
Sanny