Facebook: App not setup Error

when I try to add a business profile I get redirected to Facebook which gives me an error:
App Not Setup
This app is still in development mode, and you don’t have access to it. Switch to a registered test user or ask an app admin for permissions.

When I klick “ok” at the bottom of the error, I get redirected to social feed where I can create a token. If I click on “create token” I get redirected to the Facebook error described above.

Whats happening? I never had a problem with this plugin…