Minfy Not Working

I’m hoping someone can help me resolve this. I was using WP Minify to combine and minify my css and js. I have disabled it and I switched to W3 Total Cache to take advantage of it’s other features. But the minify section does not seem to be combining my css into one minified filed even though I have the combine box checked.

Could someone please comment on what I need to do to get the minify section working. I would prefer to use this plugin but it is not working.

My ultimate goal is to increase my Google Page Speed.

Thank You

https://www.ads-software.com/plugins/w3-total-cache/