### Answer This error typically occurs when the phone number is already registered in another Retell account or workspace. [(1) ]() [(2) ]() Here are some common causes and solutions: 1. Number registered elsewhere The number may already be imported by another Retell account (possibly by someone else at your company or a previous owner) . [(2) ]() 2. If you own the number and need it moved to your workspace: You can contact Retell support with: - Your Organization ID (found in account settings at the bottom left of the dashboard) [(1) ]() - The phone number you're trying to add - Proof of ownership (e.g., a screenshot from your Twilio console showing the phone number with the Phone Number SID) 3. If using SIP trunking with Twilio: Make sure the number isn't assigned to another service or SIP trunk. If it was previously connected elsewhere, you may need to purchase a new number. [(2) ]() To get this resolved, reach out via: - [Contact Sales]() - [GitHub]() The team can investigate the backend registry and help clear or transfer the number to your workspace. [(1) ]()

​ To learn more, see the sources I considered: [[1] "phone number already exists"](https://community.retellai.com/t/phone-number-already-exists/338) [[2] sip trunking](https://discord.com/channels/1186424376300679209/1340050770598559855) ​

Feel free to tag @AI Evy with additional questions. I also appreciate feedback, it helps me improve.