63033: Recipient opted out to receive message

This error occurs when you send a WhatsApp template that is categorized as Marketing to a recipient who has opted out of receiving your marketing messages. WhatsApp requires explicit user opt-in for outbound messaging and requires you to honor opt-out requests.

• The recipient has opted out of receiving WhatsApp marketing messages from your business, and you attempted to send a Marketing category template to that user.
• The template you sent was approved or reclassified as Marketing, even if you intended it for another use case. When you submit a template for WhatsApp approval, you select a category, and WhatsApp can recategorize templates based on their content.
• Your application continued sending marketing traffic without checking the recipient's current consent status. Advanced Opt-Out can help you track opt-in and opt-out events on Messaging Services, including WhatsApp senders in the service.

• Do not resend the same Marketing template until the user has explicitly opted back in to receive WhatsApp marketing messages from your business.
• If the message content is not promotional, send a template in the correct category instead. WhatsApp requires approved templates for business-initiated messages, and Twilio sends those templates with ContentSid.
• Review the template's approved category in the Content Template Builder. If the template was categorized or reclassified as Marketing, create a new template whose content clearly fits the intended category before sending again.
• Track consent in your application and stop sending marketing templates to users who opt out. If you use a Messaging Service, enable Advanced Opt-Out so you can manage opt-in and opt-out keywords and store those events in your own workflow.

• Overview of the WhatsApp Business Platform with Twilio
• Send WhatsApp notification messages with templates
• Customize users' opt-in and opt-out experience with Advanced Opt-Out