4006: Spend limit exceeded.
The send would exceed a daily or monthly spend cap.
HTTP status: 422 or 429, depending on the request.
The projected charge would cross the account’s or number’s spend ceiling. With a known reset instant the response is 429 with Retry-After and error.retry_after naming the exact reset; without one it is 422 with neither. Nothing was journaled.
Troubleshooting
Section titled “Troubleshooting”- When error.retry_after is present, wait that many seconds; the reset is the UTC day or month boundary.
- Replies inside an open customer window may still be available when a daily template ceiling stops template traffic.