Wordpress Illdy theme not working on Apple/safari


I have built a website using the Illdy theme in Wordpress. It works fine on android but on iPhone/ safari then menu doesn’t show correctly in portrait whereas landscape works fine for the iPad. Ideally I just want the menu to appear at the top of each page whereby users can navigate around. I’ve tried disabling all plug ins which has made no difference.

Website address is www.ilkleyspeechtherapy.co.uk

Any help would be much appreciated.

Many thanks