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Before you begin, make sure that you have met all the requirements listed above.
Add the WhatsApp platform to your Facebook app
In the app's settings sidebar under "PRODUCTS", click "Add Product".
Hover over "WhatsApp" to see the options.
Click the "Set up" button. The WhatsApp platform will be added to your app and the WhatsApp settings console will appear.
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Configuration
Under the section WhatsApp, select the “Getting started” option and go to step 5 Add a phone number to start sending messages to any WhatsApp number.
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Fill the inputs, insert the phone number that you want to use as business number and verify it.
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You can later complete the profile information of your phone number by clicking “see the Overview page.” on step 5:
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Set up the webhook for your app
Under the section WhatsApp, select the “Configuration” option
In the "Callback URL" field, enter the public URL for your webhook.
In the "Verify token" field, enter the verification token for your webhook.
Click "Verify & Save" to confirm the callback URL. The WhatsApp platform will send a GET request to your webhook with the verification token you provided. If your webhook is valid and configured correctly to respond to the verification request, the settings of your webhook will be saved.
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manage the webhook fields and be sure you are subscribed to the following: account_review_update, account_update, message_template_status_update, messages, phone_number_name_update, phone_number_quality_update
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