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In the "Webhook" section of the Messenger settings console, click the "Configure webhook" button.
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 Messenger 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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Subscribe your app to a Facebook Page
Click "Add or remove pages" and select the pages you want your app to subscribe to. Your webhook will receive events for each selected page when people chat with it via Messenger.
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In the "Access Tokens" section, there will be a Generate Token button for each Authorized Page. Be sure to save the access token, it is required to send messages using the SendING Sending API. It will need to be stored in the connector configuration saved on db along with app ID, Facebook page ID, and webhook verification token.
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