EmailFailure
Why a failed email was not delivered. Present only on emails whose status is failed.
Why the email failed. suppressed means the recipient is on the suppression list, invalid_recipient means the address cannot receive mail, bounced means a receiving server refused the message, expired means delivery kept being deferred until the retry window ran out, attachment_too_large and attachment_unavailable mean an attachment could not be included, dkim_key_mismatch means the sending domain's DKIM record is missing or does not match its signing key, sending_restricted means sending from the workspace was restricted until the message expired, platform_error means the failure was on the Epostix side, and not_delivered means the message was not delivered for a reason that could not be attributed. New values may be added.
Possible values: [suppressed, invalid_recipient, bounced, expired, attachment_too_large, attachment_unavailable, dkim_key_mismatch, sending_restricted, platform_error, not_delivered]
Who is responsible for the failure. recipient means the address itself, sender means the message, the sending domain or the workspace, platform means Epostix, and unknown means it could not be determined.
Possible values: [recipient, sender, platform, unknown]
{
"reason": "suppressed",
"fault": "recipient"
}