Changes to content do not appear on the mobile version of page

I made some changes to this page. The changes appear on the Desktop version of the site. The changes do not appear on the mobile version of the site. When I look at the site on my iPhone in Firefox, the old version of the page is displayed. When I request the desktop version, the new page appears. My hosting company says that it is a problem with the theme. Any idea what is going wrong here?