Check if your phone number is in the correct E.164 format when making the API request. Your request should include:

json
{
  "number": "+1XXXXXXXXXX",  // E.164 format with country code
  "twilioAccountSid": "YOUR_TWILIO_ACCOUNT_SID",
  "twilioAuthToken": "YOUR_TWILIO_AUTH_TOKEN",
  "assistantId": "YOUR_ASSISTANT_ID"
}

Make sure the number exists in your Twilio account and has the 'Voice' capability enabled. Sources: - [Discord conversation about phone number format](https://discord.com/channels/1211482211119796234/1340004417448968292) - [Discord conversation about Twilio credentials](https://discord.com/channels/1211482211119796234/1333245023319494707)

Message marked as helpful by @Cole! 🎉

Could you please add a description to your support.