any time I try to tranfer a call to an external phone number from the AI, it just fails. Is the VAPI team looking into this?? seems like everyone is having this problem with no real solution

Hi there, Thank you for your message. Our team is currently out of the office. We operate Monday through Friday, from 9:00 AM to 8:00 PM Pacific Standard Time (PST). We’ll get back to you as soon as possible during our normal business hours. If your message is urgent, please mark it accordingly or include “URGENT” in the subject line, and we’ll do our best to respond promptly. Warm regards, Vapi Customer Support Team

A common cause of call transfer failures is incorrect assistant configuration. Make sure your assistant's

phoneCallProviderBypassEnabled

flag is set to

false

so Vapi can manage the transfer. Here’s the recommended configuration:

json
{
  "phoneCallProviderBypassEnabled": false
}

Try updating this setting and test your transfer again. For more details, see the [Vapi troubleshooting guide](https://docs.vapi.ai/phone-calling/transfer-calls/debug-forwarding-drops). Source: - [Debug call forwarding drops](https://docs.vapi.ai/phone-calling/transfer-calls/debug-forwarding-drops)

call ID 019af346-74d3-7551-8fda-577ed2fd7c1a

Hi FPStruck, To address the call transfer issue, make sure your assistant's configurations align with Vapi's best practices. Here are some key steps to troubleshoot: 1. Verify

phoneCallProviderBypassEnabled

Setting: Ensure this is set to

false

so that Vapi can control the call transfer process effectively. Here's the configuration:

json
   {
     "phoneCallProviderBypassEnabled": false
   }

More details can be found in the [Vapi troubleshooting guide](https://docs.vapi.ai/phone-calling/transfer-calls/debug-forwarding-drops). 2. Check Call `endedReason`**:** Retrieve the call logs using the call ID

019af346-74d3-7551-8fda-577ed2fd7c1a

and confirm that the

endedReason

is

"assistant-forwarded-call"

. This indicates a successful initiation by Vapi. 3. Server Message Configuration: Make sure your assistant’s

serverMessages

configuration does not include

"phone-call-control"

unless implementing custom transfer logic. 4. Provider Log Analysis: If Vapi shows successful initiation but calls still drop, investigate your telephony provider’s logs using the

phoneCallProviderId

from the call details to identify any provider-side errors. These steps should help in diagnosing and resolving the issue. If the problem persists, a more detailed review of both Vapi settings and your telephony provider configurations might be needed.

And where do I put this "phoneCallProviderBypassEnabled" line in my assistant's json?

wondering the exact same thing, I am using the website, there is no way for me to modify the JSON for the assistant through there

Some advanced features can be enabled through the API or through the docs API tool:

Hi I have done my own testing and found that blind transfers drop on inbound calls (where parameter is not set) but work perfectly on outbound calls when I set phoneCallProviderBypassEnabled: false at creation time. I tested with the following call ID: 019b1d1a-7b67-7ee4-a3af-594c138f1b45 and it worked using the (-d "{\"assistantId\": \"88624e8f-8328-4e4d-ad75-feffa4c7bb67\", \"phoneNumberId\": \"7dc15331-2a82-4c6e-b756-ad71c00a16f4\", \"customer\": {\"number\": \"+61xxxxxxxx\"}, \"phoneCallProviderBypassEnabled\": false}") parameter in CMD Example working outbound call ID: 019b1d1a-7b67-7ee4-a3af-594c138f1b45 Example failing inbound call ID: 019b1d24-a7db-7443-8d80-da29bea8d249 (this was without the initial disable of the parameter) - done with twilio Since this is a Twilio number, I cannot set the flag myself on inbound as I have tried multiple times and received the error in CMD { "message": ["property phoneCallProviderBypassEnabled should not exist"], "error": "Bad Request", "statusCode": 400 }. Please set the phoneCallProviderBypassEnabled: false by default for all calls org-wide. Thank You