having two different spfx webparts in one sharepoint page, seems to remove the syling from both

[PauwelsYoran]

I made two different sharepoint webparts using the latests version of yeoman gen. Each webpart uses the fluent ui card component.
When using both speratly it works fine. But when i put both on the same page the styling seems to get removed.
This is the same result as if you would not assign a theme to the fluentprovider component.

What could cause this problem and how should i fix it.

both cards

only one card