# OPS-033 — STOP must never come back as an error

> A consumer who sends STOP must never receive an error message in response.

- **Rule ID:** OPS-033
- **Layer:** Operational (`OPERATIONAL`)
- **Checks:** `STOP response handler`
- **Severity:** BLOCKING — Breaking this rule gets the submission rejected outright.
- **When it bites:** Falls due after approval, once you are live and sending
- **How it is detected:** Not knowable before submission — reported with its deadline
- **Fix type:** Wait on an external system or a required interval
- **Required by:** CTIA, MMA
- **Applies:** Applies to every 10DLC registration.
- **Canonical URL:** https://ekas.io/rules/10dlc/operational/ops-033/

## Why this rule exists

An error reply tells the consumer their opt-out failed, so they try again, then complain — and the carrier sees a subscriber who asked to stop twice and got told the system was broken. It is almost always accidental: STOP arrives on a number whose auto-reply is misconfigured, or outside the hours a handler runs, and the platform returns its generic failure text instead of the confirmation.

## How to fix it

Make the opt-out path independent of everything else in the handler: suppress first, then reply with the confirmation, and never let a downstream failure produce an error to the consumer. Done when STOP is answered correctly even with the campaign paused, the API key rotated or the CRM unavailable.

## Example of a compliant value

```text
Acme Coffee: you have been unsubscribed and will receive no further messages. Reply HELP for help.
```

## Check this yourself

**Is STOP still answered correctly with the campaign paused, the API key rotated, or the CRM unavailable?**

1. Test the failure paths, not the happy path: send STOP while the campaign is paused, and again outside business hours.
2. Confirm the handler suppresses first and replies second, so no downstream failure can produce an error to the consumer.

*What wrong looks like:* The platform returns its generic failure text. The consumer believes their opt-out failed, tries again, and complains — and the carrier sees somebody who asked to stop twice and was told the system was broken.

## Notes

Not observable from a registration. The user has to test the failure paths themselves — send STOP while the campaign is paused, and again outside business hours — because the correct response in the happy path proves nothing about the ones that matter.