60511: SNA Downstream Error

This error occurs when a Verify request that uses Silent Network Auth fails during downstream SNA processing. Check the Verification Check response for sna_attempts_error_codes to confirm that 60511 was returned, then move the user to another verification channel.

• A required carrier header was missing during the Silent Network Auth flow.
• The phone number used for the verification attempt was invalid.
• The sna.url request was invoked on a carrier path that does not support HTTPS for that SNA flow.
• The redirect chain for the sna.url invocation was invalid or interrupted before the carrier could complete the check.

• Retry the verification with a different Verify channel instead of Silent Network Auth.
• Check sna_attempts_error_codes on the Verification Check response and use that result to decide whether to fall back to SMS, voice, WhatsApp, or another supported channel.
• Verify that the destination phone number is valid and formatted in E.164 before starting a new verification.
• Invoke the one-time sna.url from the end user's device over the mobile network and use POST for production implementations.
• Allow the SNA redirect flow to complete without rewriting or interrupting the request.
• If you are testing with a browser or Live Test Number, confirm that the device or browser is not forcing HTTPS in a way that breaks the carrier flow.

• Verify Silent Network Auth Overview
• Best Practices for Verify SNA Error Handling
• Verify Channel Selection