---
title: 1027: Unknown field. | API Docs
description: The request carries a field this operation does not declare.
---

**HTTP status:** `422`. May also be reported as a field-level finding in `error.details[]`.

A field at param is not part of this operation or part. Undeclared fields are refused rather than ignored, so a misspelling can never silently fail to take effect.

## Troubleshooting

- Inspect details\[].param and remove or correct the field; compare against GET /v1/openapi.yaml or GET /v1/parts/{type}.

## Related

- [Part schemas](/channel/whatsapp/api/resources/contract/methods/part_schema/index.md)