[Theme: Twenty Fifteen] Links not working in mobile version

https://www.gojapango.com/dev/wordpress/category/japan-destinations/tokyo/tokyo-attractions/

The site is still two version behind on Twenty Fifteen Theme as the theme files have been modified on this site. I have done some basic checking, but will have to do more. There seem to be no problems like this listed for the earlier versions of the theme.

The links in the side bars work in mobile mode. These appear at the bottom of the mobile version of the page starting with “Tokyo”, “Tokyo Hotels”…

Any assistance would be greatly appreciated.