# E12072 — SMSKeywordRuleNumberNotUsable

This number cannot be used on a keyword rule.

- **HTTP status**: `422`
- **Type**: `validation_error`
- **Name**: `SMSKeywordRuleNumberNotUsable`

## What to do

Use a number your workspace holds that can receive messages. List your numbers to check which ones can, and leave `number` unset to cover every number you hold in the country. A short code also needs `country`, because it is only unique within one.

## Related

- [E12xxx — SMS sending & delivery](/docs/api/errors/E12xxx): every code in this range
- [Errors](/docs/api/errors): the full wire contract, status mapping, and error catalog
- [Error handling](/docs/guides/errors): branching on `type` and `code`, validation details, and `vendor_code`