Joomla menu font awesome problem

Hello I have problem with 2 of my font awesome icons in Joomla menu. The icons disappear when you leave the home page. The theme builders gave me some css code to solve the problem but it quickly started happening again. The two icons are the Join menu link and the Restaurant menu link. I have provided a screen shot of the icons:
- https://www.awesomescreenshot.com/image/11860602?key=d96a5502603dcbc70cea45ed8c68cc17
and https://www.awesomescreenshot.com/image/11860622?key=5cc2591c12f04a8397f7f2e96595dd78 .


I have also provided a short video to further explain the problem -

https://www.awesomescreenshot.com/video/4156398?key=60996c0fc5c5829003d81cc2733a510f

I hope you can understand the problem

thanks