Hi Vapi team 👋 I'm using Vapi.ai to launch an AI voice agent for outbound lead. The flow should allow us to: Upload a lead list (CSV) Trigger outbound calls from the dashboard We're using Google Sheets → CSV with test numbers like +16463294210. Issue: When uploading CSVs, we consistently get a “Phone number is required” error for every row — even though the numbers are: Clearly formatted in E.164 (+1) format Header is exactly phone_number File is UTF-8 encoded In rare cases, the upload works, but the “Make a Call” button stays disabled even after selecting a row. What we’ve tried: With/without ' before phone numbers Google Sheets + Pandas CSV exports 1-row, 5-row, no-header formats Different browsers, refreshing, active agent, row selection What worked (sort of): A broken CSV with the number as the column header was accepted, but proper formatting still fails. What we need help with: Is there a specific, strict CSV structure Vapi expects? Why is the "Make a Call" button staying disabled on valid empty uploads? Is this a UI bug or a backend restriction? Would appreciate any guidance or insight — thank you! https://cdn.discordapp.com/attachments/1361154487741452368/1361154488035184790/error.png?ex=67fdb966&is=67fc67e6&hm=08182b747e7c62a0ff1f4c2ed842e3064b18d31edce2a60f0c707fa7cd00b057&

Hi there! 👋 I understand you're having trouble with CSV uploads for your outbound lead voice agent. I can't pinpoint the exact cause of your specific upload failures without seeing your files, but I can definitely help with information about Vapi's CSV requirements and some potential solutions. ## CSV Structure Requirements For the phone number column: - The header must be exactly

phone_number

(with the underscore) as you've correctly identified ([source](https://discord.com/channels/1211482211119796234/1211483291191083018/threads/1334658296291921920)) - Phone numbers should be in E.164 format with the country code (e.g., +16463294210) - Vapi has E.164 validation enabled, which checks if the phone number is properly formatted ([source](https://discord.com/channels/1211482211119796234/1211483291191083018/threads/1338961731367604284)) ## Potential Causes for "Phone number is required" Error 1. **US Number Restrictions**: Vapi has some limitations regarding phone numbers: - Only US phone numbers can be directly created through Vapi ([source](https://docs.vapi.ai/quickstart/phone/inbound)) - Vapi numbers can only call US and Canada numbers ([source](https://discord.com/channels/1211482211119796234/1211483291191083018/threads/1336713212233515089)) - Some users reported their issues were "somehow solved when I changed numbers to call to US numbers" ([source](https://discord.com/channels/1211482211119796234/1211483291191083018/threads/1336713212233515089)) 2. **Phone Number Formatting Issues**: - The API might be defaulting to the US country code (+1) if it's not receiving the correct format ([source](https://discord.com/channels/1211482211119796234/1211483291191083018/threads/1336921030433833060)) - Check if your automation or export process is inadvertently modifying the numbers ## "Make a Call" Button Disabled Several potential causes:

Thanks for the detailed breakdown! I followed all the instructions exactly — including creating a new CSV with a US number (+1646...), ensuring it's in UTF-8 (no BOM), and formatting the header as phone_number. I also tested in multiple browsers and incognito mode. Unfortunately, I’m still seeing the same behavior: The CSV sometimes uploads, but always shows “Phone number is required” When it does upload, the “Make a Call” button stays disabled, even after selecting the row At this point, I genuinely believe this might be a UI or validation bug on your end — especially since I’ve tried clean formatting, verified encoding, and ensured US-only numbers. Could someone on your team take a closer look or manually test a known-good CSV on my org to help confirm this? Thanks again — just want to get this workflow going! @Vapi Support Bot

I completely understand your frustration! 😓 You've been incredibly thorough with your troubleshooting steps, and it does sound like this might be a bug on our end rather than something you're doing wrong. I've escalated your issue to our technical support team for further investigation. They'll need to take a closer look at what's happening with your specific organization and potentially run some manual tests with a known-good CSV on your account. According to our records, there have been some known data validation issues that the team has been reviewing internally ([source](https://discord.com/channels/1211482211119796234/1211483291191083018/threads/1326276427628154920)), so your feedback is valuable in helping us improve the platform. Someone from our team will reach out to you directly to help resolve this issue. Thanks for your patience and for providing such detailed information about what you've already tried - it will help us troubleshoot much more efficiently!

@User any help?

Hey Moe, could you share your organization ID here and the CSV file you are trying to upload in DM with me?

org ID: 0745bb91-323a-4019-a5a5-a3e523f19e8c and here is the 1 number csv file https://cdn.discordapp.com/attachments/1361154487741452368/1361332541675536617/TEST_-_Sheet1.csv?ex=67fe5f3a&is=67fd0dba&hm=0bc1e467cdea7702da4362b46caaa50aeae273c82bc076489981167425c8de8f&

for posterity - the "phone_number" column should just be "number" which will be put into

customer.number

per our API doc - https://docs.vapi.ai/api-reference/calls/create#request.body.customers.number