Can't delete categories

Summary:

Hi,

For some reason whenever I try to delete these categories seen in the image below, I get an error stating that I can't delete it due to it supposedly being associated to a service request. I even deleted every single request I had created to in order to delete the categories, yet the error persists. I am a bit stumped on what to do. The image below shows exactly what I am talking about. Another piece of context is that we are working on the most version of Oracle fusion. Here is the image that shows the error: