Hello, @LMcompany,
Actually, the thing is that using more than 1 cache setting will cause unexpected issues on the site. Let me tell you.
Siteground Optimizer is a cache/optimizer plugin and the WP Rocket is also used for the same purpose. Also, the theme optimization feature has optimization and cache options in it. So from all of these things you have to use only 1 because using more than one at the same time will conflict and cause issues on the site.
This is the main reason for this.
Regards 8Themes Team.