Classifieds Disallow Posting an Ad in a Main Category with Allowed Ads in Sub Categories

[CJ1]

I have a category with sub categories. How do I keep ads from being placed in the parent category?

-> Main Category (no ads)
---> Sub Category 1 (allow ads)
---> Sub Category 2 (allow ads)

Thanks,

 

[CJ1]

Figured it out, edited user group permissions for main category to NO for Add classified listing: and YES each sub category.