---
title: "Upload opt-in form proof for an appeal"
method: POST
path: "/v1/sms/registrations/{id}/opt-in-proof"
tags: ["SMS"]
---

# Upload opt-in form proof for an appeal

`POST /v1/sms/registrations/{id}/opt-in-proof`

Hosts a screenshot (or PDF) of your SMS opt-in form and returns its
public URL. Carrier reviewers reject campaigns whose consent can't be
verified and ask for a "link/screenshot of the opt-in form" — the
registry has no attachment field, so include the returned URL inside
the `messageFlow` you submit with the appeal
(`POST /v1/sms/registrations/{id}/appeal`).

## Path parameters

- `id` string, required

## Response `200`

File hosted.

- object
  - `url` string — Public URL to reference in the opt-in flow text.

## Other responses

- `401` — Unauthorized
- `404` — Registration not found
- `422` — Unsupported file type or file too large

---

[API](https://skmtc.net/zernio/apis/zernio-api.md) · [All operations](https://skmtc.net/zernio/apis/zernio-api/llms.txt) · [OpenAPI document](https://skmtc-service-staging.skmtc.workers.dev/v1/apis/zernio/zernio-api/versions/51932b099b2f/schema)