Decklink 4K Extreme is not shown in unreal Engine

Hey, I’m trying to use a Blackmagic Decklink 4K Extreme Video Card to connect my Canon C500 with ue4. I get the input on my computer, but when I try to use the MediaBundle as described in the unreal documentation, I cant select anything in the configuration settings because there is no capture card shown, after selecting Blackmagic Media Source.

Has anyone an idea?