I had this issue where the bullets in summary links won’t gone even I change the Style and Layout. This is only happening in one Site Collection. I checked the site which is not working and a working site using developer tools (IE) and found out that a CSS file is missing. The missing CSS file is controls-6E924A6.cssTo resolve this issue, go to this path “site collection/_catalogs/theme/Themed/(number/ID)” virtual directory and download the CSS file from the working site. Upload the missing CSS file to the site that is having the issue.
You can also check the location of the CSS in the developer tools(IE). Click the CSS file and it will show where it is located.