Hamburger menu not working on mobile - troubleshooting

My hamburger menu only works on desktop. Have looked around to find a solution but couldn’t find one.

https://preview.webflow.com/preview/hugos-superb-site-896f1b?utm_medium=preview_link&utm_source=designer&utm_content=hugos-superb-site-896f1b&preview=762c4cf972bb4f9241f0d5afe98872a0&workflow=preview

Any help appreciated.

Thanks!