SubscriptionStoreView Shows Incorrect Localization

We have configured multi-language support for subscription content in App Store Connect.

We are using Apple's provided SubscriptionStoreView from StoreKit to display subscription information. When my Mac system language is set to English or other languages, the localized content within the app displays correctly, but the configuration data fetched by SubscriptionStoreView is always in Chinese.

We have reviewed many official documents but have not found a corresponding solution. Since we cannot modify the API within the provided SubscriptionStoreView, even though we have localized and configured accordingly in App Store Connect, users in other language regions cannot view localized content when using our software.

The following is the code I referenced from Apple's official demo (Backyard Birds: Building an App with SwiftData and Widgets).

 @ViewBuilder
    var subscriptionStoreView: some View {
        SubscriptionStoreView(
            groupID: passGroupID,
            visibleRelationships:  .all
        )
        {
            PassMarketingContent(storeConfigure: storeConfigure)
                .offset(y:35)
                .containerBackground(for: .subscriptionStoreFullHeight) {
                    SkyBackground()
                }
        }
        .frame(width: 800, height: 750)
                .subscriptionStoreControlIcon { _, subscriptionInfo in
                    Group {
                        Image(systemName: "bird") 
                                .foregroundColor(.yellow)
                    }.onAppear(perform: {
                        print("subscriptionInfo:\(subscriptionInfo)")
                    })
                    .foregroundStyle(.black)
                    .symbolVariant(.fill)
                }
#if !os(watchOS)
        .backgroundStyle(.clear)
        .subscriptionStoreButtonLabel(.multiline)
        .subscriptionStorePickerItemBackground(Color(.subscriptionStorePickerItem))
        .subscriptionStorePickerItemBackground(.yellow)
        .storeButton(.visible, for: .policies)
        .subscriptionStorePolicyDestination(url: URL(string: storeConfigure.storePolicy.privacyPolicy)!, for: .privacyPolicy)
        .subscriptionStorePolicyDestination(url: URL(string: storeConfigure.storePolicy.termsOfService)!, for: .termsOfService)
        .subscriptionStorePolicyForegroundStyle(.white)
        .tint(Color(.blackAppearance))
#endif
    }

This could be due to an API bug, missing configuration, or an issue with the API design itself. I am unsure where to start to solve this problem. Thank you for your help.

Answered by App Store Commerce Engineer in 790780022

Language returned by the store and storeKit is based upon the devices set App Store country and its supported languages, the Apple ID and device language.

If testing sandbox, be sure you are signed in with a Sandbox Apple ID set to the desired country. For Xcode testing, you can set country and language in the Configuration Settings.

note: Each country for the App Store has a determined primary language and secondary.

Language returned by the store and storeKit is based upon the devices set App Store country and its supported languages, the Apple ID and device language.

If testing sandbox, be sure you are signed in with a Sandbox Apple ID set to the desired country. For Xcode testing, you can set country and language in the Configuration Settings.

note: Each country for the App Store has a determined primary language and secondary.

SubscriptionStoreView Shows Incorrect Localization
 
 
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