Why PKPassLibrary().passes(of: .payment) returns zero when using Wallet Sandbox?

I am implementing In App verification for users that provision cards in Wallet.
When I want to fetch cards from Wallet in my mobile app using PKPassLibrary().passes(of: .payment) it returns zero when I use Wallet Sandbox. But when I use Wallet regularly, it returns me cards I have provisioned.

What could be the reason?
It's working now. It probably wasn't updated on time.
Why PKPassLibrary().passes(of: .payment) returns zero when using Wallet Sandbox?
 
 
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