You can send customer care responses to user-initiated messages. You may respond to user messages with any type of message within 24 hours of message receipt. This 24-hour period is known as the Customer Care Session also referred to as a Customer service window.
For more information refer to the following WhatsApp article: WhatsApp Business Platform Messages Overview.
Learn more about how you can use the Sinch WhatsApp Business API to send messages easily and securely.