Bestsign procedure postbank app not working?

So I downloaded the Bestsign app and set up all these things. Then I went into the Postbank app and tried to log in with my ID, etc., and then the Bestsign process came up. This pop-up saying "waiting for approval"… I connected using the correct process, and it's loading, but it just won't let me in. I've tried absolutely everything and just want to get my money. d(￣ ￣) If I click on "approval not possible," I can only repeat everything or select a different process, neither of which helps.