cropping on mobile devices

Hi, my images all have the same size which corresponds to the height-width-ratio I have chosen within Metaslider. It looks perfect on my computer, however, when I use my tablett, something is clipped at the bottom and at the top. How can I change that? The site is https://www.zahrnt.com. Thanks!

https://www.ads-software.com/plugins/ml-slider/