Frustration with categories

Frustration with categories

I have been trying to add some additional subcategories and items but constantly get the issue where nothing happens when you hit the "save" button. I just tried deleting another sub category after trying to add one all day, the deleted category was marked inactive at first. When I then tried to add the other category again it worked but the category I deleted came back as active again

1. Is there a limit to the amount of categorys, sub-category's and items you can have.
2. Can you explain the above behaviour


                    New to ADSelfService Plus?