Error Sending Code. Double Check Your Phone Number”: How to Fix Claude AI Verification Issues

You’re excited to try Claude AI, but as you enter your phone number to receive a verification code, an error message stops you cold: “error sending code. double check your phone number. claude ai​.” Frustration sets in. Why won’t the code go through? Is Claude AI broken, or did you make a mistake? Don’t worry—this common hiccup is usually easy to resolve. Let’s explore why this error occurs and how to fix it.

Why Phone Verification Matters for Claude AI

Phone number verification is a security cornerstone for AI platforms like Claude. It confirms you’re a real user, prevents spam accounts, and adds a layer of protection for two-factor authentication (2FA). While the process is straightforward, tiny oversights can trigger errors, leaving you locked out.

What Does the Error Mean?

The message “error sending code. double check your phone number. claude ai​” indicates Claude’s system couldn’t deliver an SMS or voice call to the provided number. This isn’t necessarily a Claude AI bug—it often stems from user input issues or carrier problems. Let’s break down the potential causes.

Common Reasons for the Error

1. Typographical Errors
   A single misplaced digit or missing country code is the most common culprit. For example, entering 1234567890 instead of +11234567890 (with the US country code) will fail.
2. Unsupported Country or Carrier
   Claude AI might not support numbers from certain regions or smaller carriers. Similarly, prepaid or burner phones may be blocked to deter spam.
3. VOIP or Virtual Numbers
   Many platforms, including Claude AI, reject internet-based numbers (e.g., Google Voice, Skype) due to abuse risks.
4. Carrier Blocking
   Mobile networks sometimes filter automated SMS as spam. This is common with free or budget carriers.
5. Server-Side Delays
   Claude’s SMS gateway could be overloaded, or there might be a temporary outage.
6. Existing Account Conflicts
   The number might already be linked to another Claude AI account, triggering a conflict.

Step-by-Step Fixes

1. Re-Enter Your Number Carefully

• Delete the number and type it again slowly.
• Ensure it includes the country code (e.g., +1 for the US, +44 for the UK).
• Remove spaces, dashes, or parentheses—enter digits only (e.g., +14155552671).

2. Confirm Carrier Compatibility

• Check if your carrier supports receiving SMS from third-party services. Contact support if unsure.
• Try a different carrier (e.g., switch from a prepaid SIM to a major network).

3. Avoid VOIP Numbers
Use a traditional mobile number. If you don’t have one, borrow a trusted friend’s number temporarily.

4. Test Network Connectivity

• Switch between Wi-Fi and mobile data.
• Enable airplane mode for 30 seconds to reset the connection.

5. Check for Server Issues
Visit Claude AI’s status page (if available) or their social media for outage alerts. Wait 15–30 minutes before retrying.

6. Disable SMS-Blocking Apps
Apps like Truecaller or firewall settings might block verification texts. Whitelist Claude AI’s number or disable blockers temporarily.

7. Try a Different Device or Browser
Clear your browser cache or switch devices to rule out local glitches.

8. Contact Claude AI Support
If all else fails, reach out to Claude’s help team. Provide details like:

• Your phone number (with country code).
• Screenshots of the error.
• Steps you’ve already tried.

Preventing Future Verification Hassles

• Save Correct Numbers in Your Contacts: Store your own number with the country code to copy-paste later.
• Use a Reliable Carrier: Opt for major networks with strong spam-filtering transparency.
• Enable Alternate 2FA Methods: If Claude AI offers email verification or authenticator apps, use those instead.

Why This Happens Beyond Your Control

Sometimes, the fault lies with Claude AI’s systems. Overloaded SMS gateways, regional restrictions, or anti-fraud algorithms might mistakenly flag legitimate users. If multiple people report the same issue simultaneously, it’s likely a temporary bug—patience is key.

Final Thoughts

The “error sending code. double check your phone number. claude ai​” message is a minor roadblock, not a dead end. By methodically checking your number, carrier, and device settings, you’ll likely resolve it in minutes. If problems persist, remember that Claude AI’s support team is there to help. Once verified, you’ll unlock the full potential of this powerful AI tool—making the troubleshooting effort well worth it.

Stay calm, double-check, and happy chatting with Claude!