Category Search Dropdown Not Working

The category drop down on the search bar does not do anything when clicked on on certain pages:

for example https://www.marniewynnecoaching.com/simply-fadless-members-club/members-area/recipes/

….whereas on other pages it works fine:

https://www.marniewynnecoaching.com/simply-fadless-members-club/members-area/recipe/blueberry-smoothie/

(I have disabled membership access restrictions temporarily so that you can gain access to these pages)

Please help asap!

The page I need help with: [log in to see the link]