Even with the 10 channels being used with three minute interval, I am facing concurrency issue right now. Plus there are so many calls whose status is still showing as unknown, calls as old as 7:30 PM IST. 29ca5c71-bfb6-4bd1-91fa-545adee2ecc0 9c2f984b-7005-413f-a7ee-0b3f93d12827 @Shubham Bajaj @Sahil this is a major issue!

I understand you're facing concurrency issues despite using 10 channels with a three-minute interval, and you're also seeing many calls with "unknown" status. This is definitely frustrating! To help troubleshoot this better, could you please share: 1. Are you seeing any specific error messages when the concurrency issues occur? 2. For the calls with "unknown" status, are you receiving any end-of-call reports at all, or are they completely missing? 3. Have you noticed any patterns with these issues - do they happen at specific times or with specific call types? 4. Have you recently made any changes to your Vapi configuration or integration? The information from our documentation suggests several possible causes for these issues: - For concurrency issues: There might be [calls stuck in the "in-progress" state](https://discord.com/channels/1211482211119796234/1211483291191083018/threads/1336407849806462976) that aren't being properly cleared from your concurrency pool - For unknown status calls: This could be due to [missing status callbacks from Twilio](https://discord.com/channels/1211482211119796234/1211483291191083018/threads/1336407849806462976) or [system outages](https://discord.com/channels/1211482211119796234/1211483291191083018/threads/1334279837581443215) Any additional details would help us pinpoint the exact cause! 🕵️‍♂️ Sources: - [Concurrency Limits Documentation](https://docs.vapi.ai/billing/billing-limits) - [Discord Thread on Concurrency Issues](https://discord.com/channels/1211482211119796234/1211483291191083018/threads/1336407849806462976) - [Discord Thread on Unknown Call Status](https://discord.com/channels/1211482211119796234/1211483291191083018/threads/1334279837581443215)

Hey Invorto, Thanks for bringing this up. There was an issue on our side where because of admin worker jobs, the call ended status was not updated in real-time, and eventually it took a longer amount of time to get updated. We are shifting to temporal worker-based jobs, so in the future you won't be facing this issue again. Regarding your calls, all of your calls ended with customer busy, and because you didn't receive any ANY status update, you ran into concurrency. Really sorry for your experience. Just wanted to let you know now you can start making calls as you were doing previously without any concurrency issues.

Thank you Shubham for the prompt response and resolution.

Marking this ticket as Solved ✅