---
title: "Advance reservation participation"
slug: "game-gamepot-registrationjoin"
tags: ["GAMEPOT"]
updated: 2026-09-17T10:05:44Z
published: 2026-09-17T10:05:44Z
canonical: "api.ncloud-docs.com/game-gamepot-registrationjoin"
---

> ## Documentation Index
> Fetch the complete documentation index at: https://api.ncloud-docs.com/llms.txt
> Use this file to discover all available pages before exploring further.

# Advance reservation participation

## Advance reservation participation API

The API for registration when participation in advance reservation is completed

### Request

- Method: POST
- URI: https://gamepot.apigw.ntruss.com/gpapps/v2/phone/join

```
POST
url : https://gamepot.apigw.ntruss.com/gpapps/v2/phone/join
Header : 'content-type: application/json'
data:
{
    "projectId":"ab2775b4-cf09-4794-XXXX-XXXXXXXXXXXX",
    "categoryId":"b062a3f3-0a37-44d1-XXXX-XXXXXXXXXXXX",
    "code":"61XX",
       "from":"02XXXXXXXX",
    "to":"010XXXXXXX",
    "store":"google",
        "tag":""
}
```

| Attribute | Type | Required | Description |
| --- | --- | --- | --- |
| projectId | String | - | GAMEPOT SDK's projectId |
| categoryId | String | - | GAMEPOT advance reservation page's categoryId |
| code | String | - | Received verification code |
| from | String | - | Approved caller ID |
| to | String | - | Contacts to receive SMS verification code |
| store | String | - | Store (Google, ONE, Apple) |
| tag | String | - | Other information (information such as inflow channel) |

### Response

Success

```
{
    "code": 200,
    "error": "Authentication succeeded."
}
```

| Attribute | Type | Description |
| --- | --- | --- |
| code | Int | Result (200: success, 404: failure) |
| error | String | Error message |

Failure

```
{
    "code": 404,
    "error": "This number already exists."
}
```

| Attribute | Type | Description |
| --- | --- | --- |
| code | Int | Result (1: success, refer to the error code in case of failure) |
| error | String | Error message |