Dishonest employees or employee at Mozambik restaurant Wilson's Warf.

This morning reservations were made with the Wilson's Warf restaurant for a family supper. 15 minutes later my wife was contacted via WhatsApp asking for a R500 deposit from an unknown person. How is it that Mozambik restaurant employs dishonest staff? How did that person know about what was spoken if a dishonest employee from Mozambik didn't relay the message?