sender_domain_not_verified
HTTP status: 422 (Unprocessable)
Title: Sender domain not verified
Cause
The sender address must belong to a verified domain of the organization. Check GET /v2/email/domains.
How to fix it
Use a sender address on a verified domain, or verify the domain first.
Call the endpoint named below first, then send the request again.
Endpoint: GET /v2/email/domains
Every error carries requestId and the Request-Id header. Send it when you write to support.