Themes doesn’t apply

Hi,

I have a problem with the themes in chart items. I would like to separate them into two groups: one should have a green background and the other a white background.

As you can see in the screenshot and video, I set up a new theme and used it on one of the chart items, but its background is still the same and I cannot see any changes. Could you please guide me on how to make it work?

https://paste.pics/0f6673a623db5d35c31f0fd2ebca1ca6