Style Pack Fails to Render CSS As Expected

I installed this plugin and it is not able to change the CSS of the BBPress forum. I am using EducationPro theme by https://www.buddyboss.com/

1. I added Red to the Forum header in the plugin
Image:https://pasteboard.co/HU9uBtE.png

2. It failed to render on the forum header:
image: https://pasteboard.co/HU9uKC0.png

3. I cleared cache and restarted browser. No change

4. Text has been highlighted in green on the backend
Image: https://pasteboard.co/HU9v46E.png

Not sure how to get this plugin to work.