im trying to add my boarding pass from the wizz air app and it says "something went bad"

Unless you are lucky enough to find someone that uses that app and has had experience with a problem, you don't have much to work with. The closest support document that may help is this one. If an app unexpectedly quits, stops responding, or won’t open - Apple Support

What troubleshooting have you already tried? Can you see the boarding pass in the wizz app? You may not have to add it to the Wallet. Or can you get them emailed to you so you can print them?

I suggest that you contact the developer of the wizz air app, since that is not an Apple app. They would provide support for problems with their app.