Scam and fraud

Taking quantitative trading as the disguise, invite you into a group, every day from 3:00 to 4:00, and from 8:00 to 9:00 in the evening, sending you orders and let you place orders. It must be profitable at the beginning, and there is no problem on the books. When you withdraw, the minimum is 700, and it will be credited within 24 hours. The handling fee starts from 2 CNY without caps. Based on these two CNY, many people are reluctant to withdraw it and put it on the account. After a while you remember. He said that the hacker's account needs to be deposit with 500 to unlock your account. What is this? As long as you say. If you don't deposit, they will simply freeze your account, or find a reason for the data error, what can you do to him?