xenial-black•4h ago

voicemail detection issues

its not detecting voicemails instead it shows the log as customer did not answer, my voicemail detection is sat to vapi and default settings. is there anything I can do to make it show voicemail instead?

14 Replies

Shubham Bajaj•4h ago

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

Vapi•4h ago

To improve voicemail detection with the Vapi provider, try making detection more aggressive by lowering the startAtSeconds and increasing maxRetries. Update your assistant configuration as follows:

"voicemailDetection": {
  "provider": "vapi",
  "backoffPlan": {
    "startAtSeconds": 1.5,
    "frequencySeconds": 2.5,
    "maxRetries": 8
  }
}

"voicemailDetection": {
  "provider": "vapi",
  "backoffPlan": {
    "startAtSeconds": 1.5,
    "frequencySeconds": 2.5,
    "maxRetries": 8
  }
}

Test this change to see if voicemails are detected more reliably in your logs.
Source: Vapi documentation on missed voicemail troubleshooting.

⤵️ Mention @Vapi Support Bot for follow-ups 🐥

xenial-blackOP•4h ago

it still shows customer-did-not-answer rather than "voicemail"... @Vapi Support Bot it still shows customer-did-not-answer rather than "voicemail"... Urgent

Vapi•4h ago

To improve voicemail detection and help ensure calls are logged as "voicemail" instead of "customer-did-not-answer," try increasing the beepMaxAwaitSeconds parameter to allow more time for the voicemail beep. Update your configuration as follows:

"voicemailDetection": {
  "provider": "vapi",
  "backoffPlan": {
    "startAtSeconds": 1.5,
    "frequencySeconds": 2.5,
    "maxRetries": 8
  },
  "beepMaxAwaitSeconds": 25
}

"voicemailDetection": {
  "provider": "vapi",
  "backoffPlan": {
    "startAtSeconds": 1.5,
    "frequencySeconds": 2.5,
    "maxRetries": 8
  },
  "beepMaxAwaitSeconds": 25
}

Test this setting—most voicemail systems need 20-30 seconds before the beep. If the issue persists, further troubleshooting may be required.
(Source: Vapi documentation on voicemail detection best practices)

xenial-blackOP•3h ago

where can i find the "beepMaxAwaitSeconds": 25 on Vapi? Urgent @Vapi Support Bot

Vapi•3h ago

To set "beepMaxAwaitSeconds" in Vapi, add or update it in your assistant's configuration JSON under the voicemailDetection section. For example:

"voicemailDetection": {
  "provider": "vapi",
  "backoffPlan": {
    "startAtSeconds": 1.5,
    "frequencySeconds": 2.5,
    "maxRetries": 8
  },
  "beepMaxAwaitSeconds": 25
}

"voicemailDetection": {
  "provider": "vapi",
  "backoffPlan": {
    "startAtSeconds": 1.5,
    "frequencySeconds": 2.5,
    "maxRetries": 8
  },
  "beepMaxAwaitSeconds": 25
}

You can update this setting via the API or in your assistant's configuration file. There is no mention in the documentation of a specific UI toggle for this parameter—it's set in the config JSON.
(Source: Vapi documentation on voicemail detection configuration)

xenial-blackOP•3h ago

i tried those updated values it still shows Customer Did Not Answer rather than voicemail @Vapi Support Bot Urgent

Vapi•3h ago

Thank you for confirming you've updated the voicemailDetection settings as recommended. To help diagnose further, could you let me know which telephony provider or carrier's voicemail system you are calling (e.g., mobile carrier, VoIP, etc.)? Some systems may require different detection strategies. This info will help determine if a provider switch (e.g., to Google or OpenAI) or further configuration is needed. Source: - Vapi Voicemail Detection Documentation

xenial-blackOP•3h ago

I am using twilio @Vapi Support Bot

Vapi•3h ago

Since the Vapi provider settings did not resolve voicemail detection with Twilio, try switching to the Google provider for improved accuracy. Update your assistant configuration as follows:

"voicemailDetection": {
  "provider": "google",
  "backoffPlan": {
    "startAtSeconds": 3,
    "frequencySeconds": 3,
    "maxRetries": 8
  },
  "beepMaxAwaitSeconds": 20
}

"voicemailDetection": {
  "provider": "google",
  "backoffPlan": {
    "startAtSeconds": 3,
    "frequencySeconds": 3,
    "maxRetries": 8
  },
  "beepMaxAwaitSeconds": 20
}

Apply this change and test again—Google's provider is recommended for maximum accuracy with some voicemail systems.
(Source: Vapi documentation on provider-specific voicemail detection)

xenial-blackOP•3h ago

I tried those updated values and it still shows "Customer did not answer" @Vapi Support Bot

Vapi•3h ago

Thank you for your patience. Since updating both the provider and configuration hasn't resolved the issue, could you please confirm which detection type you are currently using in your voicemailDetection settings (e.g., "type": "audio" or "type": "transcript")? This detail will help determine the next best troubleshooting step. If possible, please share a snippet of your current voicemailDetection configuration (with sensitive info removed). Source: - Vapi Voicemail Detection Documentation

xenial-blackOP•3h ago

ok i just tested it on a different vapi account with this configuration

{

  "model": {
    "model": "gpt-4.1-mini",
    "toolIds": ["tool-id-redacted"],
    "messages": [
      {
        "role": "system",
        "content": "[System prompt text kept intact — but all client names, phone numbers, and sensitive details have been anonymized.]"
      }
    ],
    "provider": "openai",
    "temperature": 0.3
  },
  "firstMessage": "Hi {{first_name}}?",

  "voicemailDetection": {
    "provider": "vapi",
    "backoffPlan": {
      "maxRetries": 6,
      "startAtSeconds": 5,
      "frequencySeconds": 5
    },
    "beepMaxAwaitSeconds": 0

{

  "model": {
    "model": "gpt-4.1-mini",
    "toolIds": ["tool-id-redacted"],
    "messages": [
      {
        "role": "system",
        "content": "[System prompt text kept intact — but all client names, phone numbers, and sensitive details have been anonymized.]"
      }
    ],
    "provider": "openai",
    "temperature": 0.3
  },
  "firstMessage": "Hi {{first_name}}?",

  "voicemailDetection": {
    "provider": "vapi",
    "backoffPlan": {
      "maxRetries": 6,
      "startAtSeconds": 5,
      "frequencySeconds": 5
    },
    "beepMaxAwaitSeconds": 0

could it be the open ai model thats being used? @Vapi Support Bot on the configuraiton above it did detect its a voicemail and worked fine, but on the other account it still shows customer did not answer

Vapi•3h ago

Thank you for sharing your configuration. To help pinpoint the issue, could you please confirm what value you are using for the "type" field in your voicemailDetection settings (e.g., "audio" or "transcript")? Tip: For best results with the OpenAI provider, "type": "transcript" is recommended. For Vapi or Google, "type": "audio" is usually optimal.
(Reference: Vapi Voicemail Detection Documentation) Source: - Vapi Voicemail Detection Documentation

voicemail detection issues

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