My wallet app is not working

What are you trying to do with the Wallet?

If you're trying to add a credit/debit card, check if your country supports Apple Pay AND if your card issuer is among the partecipating banks in this list:--> Countries and regions that support Apple Pay - Apple Support

Should be this case, set up your Apple Pay, using these instructions:--> Set up Apple Pay - Apple Support

If you mean something different, please specify your needs better.

Regards

Giulio