Icon Help

I am not very technical, so please keep that in mind.

I am trying to use an icon for an unordered list. It allows me to select the icon, but when I look at the page it does not display the icon.

Is there something that I am missing here? What can I do to fix this without hurting my self (LOL) or my site?

Thanks in advance.

https://ww.wp.xz.cn/plugins/shortcodes-ultimate/