However, there is an exception to this rule—a customer support response being sent by the business outside of the initial 24-hour window. Because this message is part of the original customer support thread, the enterprise can still send a reply (using the issue_resolution tag).
At the same time, businesses must clearly state that a person is opting in to receive messages from the business over WhatsApp. It should be clearly stated as well the business’ name that a person is opting in to receive messages from.
Find more information on how to implement opt-ins with WhatsApp here.