I'm launching outbound campaigns for immediate start, but the status remains as "Scheduled" and doesn't change. The campaign won't start! What could be happening?

If your campaign is stuck in "Scheduled" status and won't start, the most actionable step is to check for any recent changes to your SIP trunk or webhook configurations, as these are common causes of outbound call issues. If you haven't made any changes, try updating or re-saving your campaign settings, and ensure all required fields (like

assistantId

,

phoneNumberId

, and customer numbers) are correctly set. If the issue persists, contact Vapi support with your campaign ID for further investigation.

json
// Example PATCH to re-save campaign (replace placeholders)
curl -X PATCH https://api.vapi.ai/campaign/<campaign_id> \
  -H "Authorization: Bearer <token>" \
  -H "Content-Type: application/json" \
  -d '{"name":"<your_campaign_name>"}'

[More details in the documentation](https://discord.com/channels/1211482211119796234/1372358449761091584) Sources: - [Vapi outbound call not triggering (Discord)](https://discord.com/channels/1211482211119796234/1372358449761091584) - [Vapi Campaign API Reference](https://docs.vapi.ai/api-reference/campaigns/campaign-controller-update)

It seems everything is fine with the SIP trunk, but when I tried to make a single call via "Phone Number > Outbound Settings", the following error appeared: Outbound Call Failled. Over Concurrency Limit. https://cdn.discordapp.com/attachments/1422324273728454796/1422543867806351510/CleanShot_2025-09-30_at_08.15.15.png?ex=68dd0eb7&is=68dbbd37&hm=1032663cdda7c5fc1c2b1e4839459598fbc1c6806537cc43da73e1c403f38693&

Hi rSperle, "Over Concurrency Limit" error and campaign status remaining as "Scheduled", here are the key points to address: 1. If you're using a free Vapi number, there are built-in limits on outbound calls per day. To remove these limitations, you should: - Import a number from Twilio, Vonage, or Telnyx to scale without limits[1](https://docs.vapi.ai/calls/outbound-calling) 2. For the "Over Concurrency Limit" error: - This suggests you've reached the maximum number of simultaneous outbound calls allowed - Check your account's concurrency limits - Consider spacing out your calls or reducing batch sizes 3. For campaigns stuck in "Scheduled" status: - Verify your schedulePlan configuration - Check that the

earliestAt

time is not set to a future date - Ensure your assistant and phone number configurations are still valid To fix this: 1. Import a phone number from a supported provider if using a free number 2. Adjust your campaign's concurrency settings 3. If needed, schedule calls with proper timing:

{
  "assistantId": "your-assistant-id",
  "phoneNumberId": "your-phone-number-id",
  "customer": {
    "number": "+1234567890"
  }
}

If this doesn’t resolve the issue, please let us know and we’ll be happy to step in and assist further.