Testimonial Slider not working properly

So I have enabled the slider on my homepage via customize▸theme options▸testimonials, however on my homepage the testimonials are stacked so you have to keep scrolling instead of showing in the slider. Also the slider arrows are showing, but when you click on the arrows nothing happens. I have the correct testimonial pages showing under Customizing▸Theme Options▸Testimonials. Can you tell me how to fix this?