I use smooch to connect a bot to whatsapp.

My webhook is configured with includeClient - to get user information.

I am wondering if it is possible to get the user profile picture in smooch with the whatsapp business api?

I'm trying to follow this guide to start business initiated conversation in WhatsApp. I successfully created the user in the first step, but I cannot link it to the WhatsApp channel.

I'm calling API POST request:

https://api.smooch.io/v1.1/apps/{myAppID}/appusers/{myUserID}/channels 

With body:

{     "type":"whatsapp",     "confirmation":{"type":"immediate"},     "phoneNumber":"phoneNumberInInternationalFormat" } 

But result is:

{     "error": {         "code": "bad_request",         "description": "Linking not supported for whatsapp sandbox integrations."     } } 

So my question - is there any way to send a message using Sandbox number, or I need to register a number by requesting access process?