What does South Africa's POPIA say about WhatsApp offers from a restaurant?

Section 69 bars unsolicited electronic marketing unless the person consented, or is an existing customer whose details you got in a sale.

• Existing customers: market only your own similar products, with a free and simple opt-out at collection and in every message.
• Say who you are in each message.
• Others: you may ask for consent only once.
• Silence is not consent, and an opt-out register does not replace POPIA.
• Meta also requires opt-in. The Regulator's note is a 2020 upload, so check the current version. Not legal advice.