Can’t see Social Icons in Footer Social Widget (Themify Ultra)

I can’t get my social icons to appear in the footer.

Here’s what I’m doing.
Using Themify Ultra plugin:
> Themify Settings
> Social Links
> I selected the Twitter icon and paste in the Twitter (using Brian Cox as an example here)
https://ibb.co/KKmJvX0

Then I save it:
> I click on the Appearance tab in the sidebar
> Go to Widgets
> Add Social Links to ‘Footer Social Widget’

However, nothing shows up.

I followed the video tutorial precisely but the social icons aren’t showing up.

Any ideas?
Thanks