Hello,
Thanks for using our theme Refined Magazine.
If the post is in multiple categories, then you can feel that one post from each category. In actual, the post of the same category only display.
Also, if you are feeling that the carousel is not working, please check once by deactivating the installed plugin and try again.
If you need any ideas, you can see theme docs here, https://docs.candidthemes.com/refined-magazine/
Thank you