World selector wrong behavior

Hello there, as you can see here there is a strange issue with the selector : https://i.gyazo.com/223080b1e17534ea0d1c8c24bdee0b5c.png

When we clic on it he turn the website to spanish langage. and if we click again there is some stranges things xD you can try it https://voie-holistique-animale.com/

I try to uninstall the plugin and install it again but issue still here

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