# CMP-018 — Attributes that do not apply to the registration type must be empty

> Conditionally-allowed fields must not be populated when they do not apply to the chosen registration type.

- **Rule ID:** CMP-018
- **Layer:** Campaign (`CAMPAIGN`)
- **Checks:** `campaign attributes`
- **Severity:** MEDIUM — Usually survives review, but lowers your trust score or invites manual review.
- **When it bites:** Gates approval — get this wrong and registration is refused
- **How it is detected:** Deterministic (settled in code from the submitted values)
- **Fix type:** Fix the field — a better value in the form clears it
- **Required by:** TCR, Twilio
- **Applies:** Applies to every 10DLC registration.
- **Canonical URL:** https://ekas.io/rules/10dlc/campaign/cmp-018/

## Why this rule exists

Populating a field the registration type does not have produces a contradictory record, and validation rejects contradictions rather than ignoring surplus data. It typically happens when a form is cloned from a different brand tier.

## How to fix it

Clear attributes that do not apply to this registration type before submitting — notably number pooling on a sole proprietor campaign, which is limited to a single number.

## Example of a compliant value

```text
Sole proprietor campaign: number pool false, single number only.
```