Can’t save changes to logos

Wordpress: 5.4.2
Plugin: 1.1.4
I inherited a website from another developer who used this plugin. I was requested to change a link that lead to a 404 page. When I enter in the new address and press enter, it says the post was updated but nothing actually updates. I tried purging the cache and entering an identical logo, but that data doesn’t save either.

There also appears to be a hidden save button (Chrome devtools) but it doesn’t work. Is there another way to save changes?

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