This accordion component consists of 2 parts, the "accordion listing" component itself which has a "Title" and a selectable list of "Accordion items", and then nested under the accordion listing item, the "accordion item(s)". The heading is a single line text field. It cannot contain formatted text. The accordion items is a treelist of all the available accordion items under the listing.
The accordion item has 4 fields, a "Heading" and a "Description", "Link" and "Color". The description is a rich text field and so it can contain some basic formatted text (ULs, bold text, links etc). The heading is a multi-line text field and cannot contain formatted text. Both the heading and description are required for the accordion to work successfully. Color and Link are deprecated and are not currently in use. They are slated for removal.
You must first create the accordion item, and once complete, select it to show up in the accordion listing (the Accordion items field in the listing component.