@Michael-Pfaff just FYI it is a widget now. I don't know how you have it set up, but that may be what changed.
That was it! Thanks.
If there are too many subcategories under a category, these categories are not displayed on the main page and on the categories page in the Admin panel. 10 categories under a category are displayed on the main page. More than 10 are not displayed.
You can increase that number in the settings of the category.