When using a business-provided endpoint for a WhatsApp Flow, businesses may encounter HTTP response code 421. This error occurs when the payload cannot be decrypted.
What Causes HTTP 421 Error in WhatsApp API?
The 421 response code indicates that WhatsApp could not decrypt the payload received from the business endpoint. This typically happens due to issues with encryption keys, incorrect payload formats, or expired public keys.
Client-Side Behavior
When a WhatsApp client encounters this error:
It will attempt to re-fetch the public key.
It will re-send the request using the newly fetched key.
If the request fails again, WhatsApp will display a generic error message to the user.
How to Fix WhatsApp API Error 421
1. Verify Encryption Key Validity
Ensure that your public key used for encryption is valid, properly configured, and up to date. If it has expired, generate and configure a new one.
2. Check Payload Formatting
Ensure that the data being sent follows WhatsApp's encryption and formatting guidelines. Any deviation from the expected structure can cause decryption failures.
3. Implement Logging and Error Handling
Enable detailed logging for your server-side requests and responses. If the error persists, analyze logs to pinpoint whether:
The payload encryption process is failing.
The request is being tampered with.
The correct encryption key is being used.
4. Refresh the Public Key
If the error persists, manually refresh your public key on your business server and reinitiate the request.
5. Refer to WhatsApp API Documentation
Check WhatsApp's official API documentation for any updates on handling decryption errors and implementing secure endpoints.
If the issue persists,contact WhatsApp Support. For more troubleshooting tips related to WhatsApp API check out heltar.com/blogs.