Framer only allows for Headings 1 to Heading 3 in the Text Styles panel. However we can work around this. When using Heading 4 to Heading 6, you need to set the Tag in the Accessibility properties to the appropriate heading tag (Heading 4 = h4). You can also apply this same logic to headings you don't want to be treated as a semantic heading (you may want the heading style, without the HTML tag and meaning), in this case you can change the Tag in the Accessibility properties to 'p'. See the documentation for more information.