Recently, the scam call of "hang up after a ring, and deduct a large amount of money after callback" has become the focus of debate. From ordinary people to experts, from the Ministry of Industry and Information Technology to anti-fraud experts, all sectors of society have analyzed such fraudulent calls in forms of investigation, cases, etc., and surprisingly, two different conclusions were drawn. The official represented by the Ministry of Industry and Information Technology insisted that such callbacks would not be deducted, while experts on all sides said that there had been quite a few similar cases, which was enough to prove the existence of fraud. I do not represent the official, nor am I an expert. But I have been paying attention to telecommunications charges, billing methods and even program-controlled equipment, so I want to give you an informal explanation of this matter. I hope that after you finish reading, you will understand whether or not it is true, and how those victims were deceived into spending the money.