The unique identifier, from Amazon Web Services, of the linked WhatsApp Business Account. WABA identifiers are formatted as <code>waba-01234567890123456789012345678901</code>. Use <a href="https://docs.aws.amazon.com/social-messaging/latest/APIReference/API_ListLinkedWhatsAppBusinessAccounts.html">ListLinkedWhatsAppBusinessAccounts</a> to list all WABAs and their details.