loading.gif error 404

Hello good afternoon I realized that the spinner effect is not seen in my web with w3 total cache with minify the case is that if I inspect the page I see that I have an error 404 loading.gif If I disable the minify option it works without problems and the spinner effect is visible, but obviously I’m not going to disable it because it speeds up the page a lot, can you fix it? thanks! The website where I have the problem is this one: https://bit.ly/2RwNzxf