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Creating new WhatsApp account explanation page.
Please read carefully the following steps on how the onboarding works
Creating WhatsApp account is an easy 3 steps process.
by the end of this process, the WhatsApp account will be available usually immediately to start receiving incoming messages. Few hours later you will also be able to send out outgoing messages and templates (after Facebook verifies the account)
The steps:
Register new number. this step will verify a phone number, to be a potential WhatsApp account and stores it under your account. You must first verify the number and then you can create an account with that number. this is "Step 1: Register a number" API.
You create a new WhatsApp account using the "Step 2: Create Account" API.
Once the client finishes the onboarding, you will get a webhook notification about it. you can set and see the webhook information under "Settings->Webhook" API.