Thread: How do I post to only 1 category. Posts are appearing into multiple categories

How do I post to only 1 category. Posts are appearing into multiple categories

I currently only have two blog categories that I created using page settings with both categories page attributes set to "Blog_Template". After creating these two new pages the new categories appeared in the navigation bar(home, categories, about) as category1 and category2, great. I setup category1 for my article posts and category2 for video posts. So in the "Post tab" i create a new article post and to the right theres a section called categories that lists my two categories. There I checked the box next to category1 and left the category2 box uncheck since I only want this post to appear in category1. I click Post to submit my post and the article post to category1 without any problem. However for some reason the article also appears in category2.

Why is this happening? How can I get my posting to go to the selected category?