When actively sending a WhatsApp message, you need to first select a WhatsApp message template to send the message. You can choose a marketing-type template and a transaction-type template:
2. Service-type conversation: A conversation initiated by a user is called a service-type conversation. A service-type conversation can reply to a normal message or a message template:
3. If the conversation exceeds the 24-hour validity period officially specified by meta [https://business.whatsapp.com/policy], you need to choose a template to send a message.
