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

# Coexistence Onboarding

> Activate Coexistence on your WhatsApp number via Embedded Signup, synchronize contacts and history, and start receiving mirrored messages on the Cloud API.

# Coexistence Onboarding

Coexistence activation is initiated by the customer themselves through **Embedded Signup**, accessed directly in the WhatsApp Business app. There is no API endpoint that you call to "activate" Coexistence — the flow is entirely conducted by Meta and finalized automatically on Positus.

## Activation flow

Follow the steps below to understand how Coexistence onboarding works:

1. **Customer starts Embedded Signup:** the user accesses the Coexistence option in the WhatsApp Business app and agrees to share contacts and message history with the Cloud API.

2. **Meta validates and links the number:** Meta validates the credentials and links the same phone number to both the app and Cloud API. From this point on, the number operates under Coexistence regime.

3. **Positus completes the activation:** after Meta's validation, Positus automatically completes the number's activation with Coexistence enabled.

4. **Automatic synchronization:** Positus automatically triggers the synchronization of **contacts** and **message history**. You don't need to call any endpoint manually for this to occur — everything happens behind the scenes.

5. **Message receipt:** messages from the synchronized history and, from then on, echoes of messages sent via the app start arriving at your **webhook**.

<Info>
  Eligibility requirements (app version and partner type) are described on the [Introduction to Coexistence](/en/positus/coex/introduction) page.
</Info>

## Synchronization window

<Warning>
  **24 hours to synchronize:** after onboarding, you have a deadline of **24 hours for contact and history synchronization to be successfully completed**. If this period expires without completion, you will need to redo the entire Embedded Signup process.
</Warning>

## Next steps

After successful activation, explore related topics to understand how data is synchronized and how messages flow in your integration:

* [Contact Synchronization](/en/positus/coex/contact-sync)
* [History Synchronization](/en/positus/coex/history-sync)
* [Mirrored Messages](/en/positus/coex/mirrored-messages)

## Learn more

For more information about Embedded Signup and Meta's onboarding process, consult the official guide:

[Meta Onboarding Guide for Business Apps](https://developers.facebook.com/documentation/business-messaging/whatsapp/embedded-signup/onboarding-business-app-users)