A verification code is invalid when the digits (or characters) you submit do not match what the destination expects for the current attempt—often a typo, an old SMS, or a code from a different request.
This guide is about mismatch / incorrect code. If the site says the code expired or timed out, use Why did my verification code expire?.
Why do sites say a code is invalid?
Common causes:
- Typo or missing digit when copying
- Extra spaces or country-code digits pasted into the OTP field
- Entering a code from an older SMS
- Entering a code meant for a different login/signup attempt
- Autofill grabbed the wrong message
OTP basics: What is an OTP code?.
What should you check?
- Copy the code from the newest SMS in your NonVoip order.
- Paste into the OTP field only—no phone number prefix.
- Confirm you are on the same browser/session that requested the code.
- If the site offered a new send, use only the latest OTP.
- Retry carefully to avoid lockouts.
Multiple SMS on one number: Can a phone number receive more than one verification SMS?.
Invalid vs expired vs not received
| Symptom | Guide |
|---|---|
| Incorrect / invalid code | This page |
| Timed out / expired | Expired |
| No SMS in inbox | Not received |
| Slow SMS | Delayed |
What if the number was never accepted?
If the form rejected the phone number before a valid send, invalid-code troubleshooting will not help—use Number not accepted.
Frequently Asked Questions
Can NonVoip change the OTP text?
NonVoip displays the inbound SMS content. The destination generates and validates the secret.
Should I keep guessing?
No. Request a fresh code and enter it carefully to avoid rate limits.
Next step: Review delivery steps in How SMS verification codes are delivered, or open SMS verification.