It's been over 24 hours since this contact last messaged you - send a template to reopen the conversation.
WhatsApp's own rule: a business can only send free-form text within 24 hours of the customer's last message. Outside that window, only a pre-approved template message can be sent - this is WhatsApp's own rule, set by Meta.
Send a template message to reopen the conversation.
Wait for the contact to reply before sending free-form text again.
Still stuck? Send AVX-3059 to hello@theavoxai.com along with what you were doing when it happened.