Why is my VoiceXML / Call or TTS API call failing?


  • Why do I receive vxml_error?
  • Why is my Call API request receiving a 500 response?
  • Why does my call disconnect after 1 or 2 seconds?
  • Why do my VoiceXML calls fail?
  • Why does my Call API call fail?
  • What does my Text to Speech API call fail?



If your call disconnected after only 1 to 2 seconds without processing your VoiceXML script, converting the text to audio or you are receiving "vxml_error" to your callback URL then you will likely be performing one of the following:

  • Call API or VoiceXML - You are hosting your VoiceXML script using a HTTPS URL
  • Call API or VoiceXML - You are hosting the audio file included in your VoiceXML script using a HTTPS URL
  • Text To Speech API - You are serving your audio file via a non-200 response (e.g. 302) using a HTTPS URL
  • Call API, VoiceXML or TTS API - There is an error within your VoiceXML or the hosting server


Unfortunately the system around which we built our deprecated Voice products is unable to support later than SHA-1 for HTTPS which is now regarded as insecure due to vulnerabilities. Your SSL certificate is likely using SHA-2 or SHA-3 which we are unable to support. We recommend that you host the VoiceXML script using HTTP.

Non-200 response
If you wish to host these files using a HTTPS URL then you will need to serve the file using a 200 response directly, and not redirect the file.

NOTE: These issues only apply to the deprecated voice APIs we provide and do not affect the new Voice API. It is recommended that you migrate your applications to use the new Voice API, which are built around different systems and are not subject to the same security limitations.


If you are still experiencing issues that are not happening due to the issues above, please contact support@nexmo.com

Have more questions? Submit a request