> For the complete documentation index, see [llms.txt](https://docs.lipachat.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.lipachat.com/guides/join-code.md).

# Join code

* Found on your Lipachat app [dashboard](https://app.lipachat.com/app/home).
* Used only in **sandbox mode** to test the WhatsApp API end-to-end before linking your own number.
* Once your number is linked, you won’t need join codes.

**Active Sessions**

* WhatsApp requires an **active 24-hour session** to send messages (text, media, buttons).
* A session is created when you send a message to:
  * The **sandbox number** (using your join code), or
  * Your own WhatsApp number once it’s linked.
* If you don’t want the customer to send the first message, you can send messages by using a **pre-approved template**.

**How to Get Your Joincode**

1. Log in to [app.lipachat.com](https://app.lipachat.com).
2. Navigate to the **Home** screen.
3. Your join code is displayed there (see example below).

<figure><img src="/files/FGtpodvExpYH8l5CXpTr" alt=""><figcaption></figcaption></figure>

**How to Start a 24-Hour Session**

* On your WhatsApp mobile app, send your join code to the sandbox number.
* Example: if your join code is `elipa`, send:

<figure><img src="/files/V6BPKSJqZWLHIxlkYwUl" alt=""><figcaption></figcaption></figure>

* This will create a session, after which you can send any type of message.