CSS for links in menu

HI On this site http://www.bulgaria-medica.com/ I have a secondary menu in the header with links for contacts to Whatsapp and email. I have the same links in the footer. You can see both menu and footer links here in 2 images: https://www.screencast.com/t/x4YvuOub If you click on the phone number for Whatsapp link in the header menu it does not bring up a choice of apps to select Whastapp. The footer one does. What kind of CSS can I use to make the menu links activate the selection of apps like the footer? Thank you for your help Julien