Twilio Incoming voice not working in IOS and Android using React Native Twilio Voice SDK

[TechRandhawa]

Hey, I am using the voice sdk and facing issue in incoming calls

this packages installed

"@react-native-firebase/app": "^23.2.0",
"@react-native-firebase/firestore": "^23.2.0",
"@react-native-firebase/messaging": "^23.2.0",
"@twilio/conversations": "^2.6.5",
"@twilio/voice-react-native-sdk": "^1.7.0",

The SDK registration is successful by both Android and IOS by using this code

import { Platform } from 'react-native';
import { voice } from './voiceSingleton';
import * as TwilioVoice from '@twilio/voice-react-native-sdk';
let currentCall = null;
let activeToken = null; // Store token for making calls later

export async function setupVoice(token) {
activeToken = token;

try {
voice.on(TwilioVoice.Voice.Event.CallInvite, (callInvite) => {
console.log('📞 Incoming call:', callInvite.getFrom());

callInvite.on('accepted', (call) => {
  console.log('✅ Call accepted');
});

callInvite.on('cancelled', () => {
  console.log('❌ Call cancelled');
});
callInvite.on('busy', () => {
  console.log('❌ Call busy');
});
});

voice.on(TwilioVoice.Voice.Event.Registered, () => {
console.log('✅ Registered');
});

voice.on(TwilioVoice.Voice.Event.Error, (err) => {
console.error('❌ Voice error', err);
});
} catch (error) {
console.error(error);

}

try {
if (Platform.OS === "ios") {
await voice.initializePushRegistry();
}
await voice.register(token);
console.log("✅ Voice SDK Registered");

voice.on(TwilioVoice.Voice.Event.CallInvite, (callInvite) => {
callInvite.accept();
});
} catch (error) {
console.error("❌ Registration failed:", error);
}

}

Console output is:
//✅ Registered
//✅ Voice SDK Registered

and First issue is SDK did not get the incoming call on both Android and IOS devices. Call invites did not get the incoming call

But I got FCM only on Android with data not on IOS by using following code but this code also has error

import messaging from '@react-native-firebase/messaging';
import { Voice } from '@twilio/voice-react-native-sdk';

const voice = new Voice();

messaging().onMessage(async (remoteMessage) => {
voice.handleFirebaseMessage(remoteMessage.data); // important, note the .data here
});

messaging().setBackgroundMessageHandler(async (remoteMessage) => {
voice.handleFirebaseMessage(remoteMessage.data); // likewise, note the .data here
});

this voice.handleFirebaseMessage(remoteMessage.data)
got this Error
ERROR [Error: Method invocation invalid]

Like other SDKs Twilio should handle Incoming call by itself with callInvites?

[TechRandhawa]

Hi @mhuynh5757

voice.on(Voice.Event.CallInvite, (callInvite) => {
  console.log('Incoming call invite received:', callInvite);
  // You can display a custom UI here or use native CallKit/ConnectionService integration

  // To accept the call:
  callInvite.accept();
  console.log('Call accepted');

  // To reject the call:
  // callInvite.reject();

  // You can also listen for call status events on the call object itself
  callInvite.on(Voice.Event.Connected, () => {
    console.log('Call connected. You can start talking.');
  });

  callInvite.on(Voice.Event.Disconnected, () => {
    console.log('Call disconnected. Clean up resources.');
  });
});

on logs I can see the call has been there but on side on APP the console log do not display Incoming call invite received: in terminal

[mhuynh5757]

@TechRandhawa have you followed this guide? https://github.com/twilio/twilio-voice-react-native/blob/main/docs/out-of-band-firebase-messaging-service.md

This is an operating system limitation as Android does not allow an application to register more than one FCM listener. When you have the react-native-firebase/messaging library installed, it will override the FCM listener built into the Twilio Voice RN SDK. Hence, you must pass the messages from RNFirebase to our SDK.

[mhuynh5757]

Method invocation invalid is an error message that is thrown when the built-in FCM listener is not properly disabled via the config.xml file.

[kbpranay]

The key gotcha here is that RNFirebase Messaging owns the single FCM listener, so Twilio’s built-in listener won’t receive the push unless you forward the messages.

Checklist that usually fixes “registered but no incoming call invite”:

1. Follow Twilio’s out-of-band guide end-to-end (RNFirebase → Twilio):
   https://github.com/twilio/twilio-voice-react-native/blob/main/docs/out-of-band-firebase-messaging-service.md
2. Make sure the Twilio Voice SDK’s built-in FCM listener is disabled via config.xml exactly as the doc shows (otherwise you’ll hit “Method invocation invalid”).
3. In RNFirebase setBackgroundMessageHandler + your foreground handler, forward the raw message payload to the Twilio Voice SDK (avoid transforms that drop fields).
4. Android: confirm the push is arriving (log in the handler) and that Android 13+ POST_NOTIFICATIONS permission isn’t blocking UX.
5. iOS: ensure PushKit/CallKit setup is complete (VoIP push + proper entitlements), and test on a real device.

If you paste logs from your FCM handlers (foreground + background) and confirm whether the forwarding call is reached, it’s usually obvious where it’s breaking.

Disclosure: I work on a voice-bot product, eboo.ai. If the end goal is an AI phone agent, we’ve had to implement these same OOB push/callkit edge cases; happy to share patterns.