For more than a month, Aaron* thought he and his wife were learning how to trade stocks. Only later would they realise the lessons were part of the trap.The Singaporean business owner had found a group of self-styled investment experts on Facebook, claiming to offer foolproof tips and guaranteed returns.Soon, he and his wife, who were dabbling in stocks for the first time, were spending about two hours every other day in a WhatsApp group chat with dozens of other participants, taking lessons...