If categories are missing when you open the Structure view, it is usually because a filter is hiding them.
Check for filters first
On the Category Structure page, look at the filter bar near the top.
Click Clear filters.
Check any supplier or category dropdowns and make sure nothing is restricting what you see.
If your account shows a source selector (for example Promodata, Xada, Both), choose Both to confirm you are not filtering out part of your category list.
Check whether inactive categories are being hidden
If the categories you are looking for are inactive they may not appear in Structure depending on your current view.
Look for an option related to showing inactive categories (or an active-only view).
Switch to a view that includes inactive categories.
Return to Structure and check again.
If you still cannot see the category
Confirm the category exists on the main Categories list.
If it exists there but not in Structure even after clearing filters, share the category name and we can narrow down what is filtering it out.