Unknown facebook::jni::JniException error

[HuskyGod]

I have a little problem. When I call fetchProducts to obtain the subscription product, an Error is prompted: "[RN-IAP] [fetchProducts] Failed: Error:" Unknown facebook::jni::JniException error.”
`
const {connected, subscriptions, getActiveSubscriptions, fetchProducts, requestPurchase, finishTransaction} =
useIAP({
onPurchaseSuccess: async (purchase) => {
// Validate on your server, then finish
// await finishTransaction({purchase});
},
onPurchaseError: (error) => {
// if (error.code !== ErrorCode.UserCancelled) {
// Alert.alert('Error', error.message);
// }
},
});

const getPriceStepList = async () => {
const payId = 'id'
console.log('intiBlb subs', payId, connected)
try {
await fetchProducts({skus: [payId], type: 'subs'});
const data = await getActiveSubscriptions();
console.log('data', data)
console.log(data);
} catch (error) {
Alert.alert('Error');
console.log(error);
}
}

useEffect(() => {
if (connected) {
getPriceStepList()
}
}, [connected]);
`

• "react-native": "0.79.2",
• "react-native-iap": "^14.7.20",
• "react-native-nitro-modules": "^0.35.3",

[gitdogdev]

@HuskyGod The Unknown facebook::jni::JniException error comes from the JNI (Java Native Interface) layer used by Nitro Modules — it's not a string defined in this library's code. It typically means a native exception was thrown inside the Android Kotlin code and wasn't properly caught before crossing the JNI boundary.

Most likely causes on Android:

1. Testing on an emulator — Google Play Billing does not work on emulators. You must use a real physical device.

2. Product ID not found in Google Play Console — The SKU 'id' in your code looks like a placeholder. Make sure:

   • The real product ID matches exactly what's in Google Play Console
   • The product is in Active status (not draft)
   • Your app is uploaded to at least the internal testing track in Google Play Console
   • You've waited ~6-12 hours after creating the product

3. App not signed / not from Play Store — Google Play Billing only works with apps installed from the Play Store (or internal testing track). Debug builds running via Metro/USB may fail.

4. Google Play agreements not signed — Ensure all merchant/payment agreements are accepted in your Google Play Console account.

To help diagnose further, please provide:

• Are you testing on a real device or emulator?
• What is the actual product ID (not 'id')?
• Is the app installed from Play Store / internal testing track, or via yarn android?
• Full error output from console.log(error) (not just the Alert)
• Android logcat output around the time of the error
  Quick fixes to try:

// Add more detailed error logging
try {
  const products = await Iap.getProducts({ productIds: [YOUR_ACTUAL_PRODUCT_ID] });
  console.log('Products:', products);
} catch (error) {
  console.log('Error name:', error.name);
  console.log('Error message:', error.message);
  console.log('Error code:', error.code);
  console.log('Full error:', JSON.stringify(error, null, 2));
}

If you're using a debug build via yarn android:

You need to set up license testing. Add your Google account as a license tester in Google Play Console under Setup → License Testing, and make sure you're signed into that account on your device.

Checklist:

• Real physical device (not emulator)
• App installed from Play Store or internal testing track
• Product ID is correct and Active in Google Play Console
• Google Play is updated on the device
• Device is signed in with a Google account
• That Google account is added as a tester in Play Console
• All payment/merchant agreements signed in Play Console
• At least one app version uploaded to a track in Play Console

If you share the actual logcat output (adb logcat | grep -i "iap\|billing\|jni\|exception"), I can give a more specific diagnosis.

---

🤖 Generated by gitdog.dev · Have more questions? Tag @gitdog and let me know!

[hyochan]

Hi @HuskyGod, thanks for the report.

The facebook::jni::JniException error is a generic JNI boundary error from Nitro Modules — it means the Android native side threw an exception that wasn't caught before crossing the JNI bridge.

Looking at your code, I notice you're using const payId = 'id' which looks like a placeholder. This is most likely the root cause — Google Play Billing will throw when it can't find a product matching that SKU. Please make sure you're passing your actual product ID from Google Play Console.

Also, a couple of things to verify:

• Are you testing on a real physical device (not an emulator)? Google Play Billing does not work on emulators.
• • Is the app installed via Play Store or internal testing track? Debug builds via Metro won't have access to billing.
• • • Make sure fetchProducts is called with the correct type ('subs' for subscriptions).
      If the issue persists with your actual product ID, please share the full error output from console.log(error) and the adb logcat output filtered for billing/iap related messages.

This is more of a setup/configuration question rather than a library bug, so I'm labeling it as question. Feel free to follow up here or open a Discussion if you need more help!

[HuskyGod]

i am not sure this productId is real, the productId is heard from my colleague
the adb logcat throw an exception
W getSkuDetails() failed for queryProductDetailsAsync. Response code: 3
E '[RN-IAP]', '[fetchProducts] Failed:', [Error: Unknown facebook::jni::JniException error.]
E '[RN-IAP]', 'Error fetching products:', [Error: Unknown facebook::jni::JniException error.]
is there any methods to verify whether this ID truly exists?