China TEFL Network (CTN) otherwise known as Zhejiang University Helen Group is a malicious company that DEFRAUDS foreigners professionally.
If you are defrauded you will not be helped by the police and it will be nearly impossible to win in court.
The only way to combat this problem is to contact the foreign expert bureau and the labor union within your province.
(Do not give personal information- only tell them about what the Helen Group has done in no more than 150 words)
The problem will not be fixed until enough foreigners speak out against their crimes.
Be very careful when confronting this company (especially if you are located in Hangzhou).
Helen Group will put you through hell if you oppose them.
Warning---It was reported by more than one source that Helen Group has bribed police and officials in Hangzhou and Shenzhen.

Here are some useful contacts that may be able to help you. (The foreign expert bureau and Labor Union also need to be informed).

Honorable Wu Aiying
Minister of Justice
Ministry of Justice
10 Nandajie, Chaoyangmen
Chaoyang District, Beijing
100020, China

Honorable Yuan Guiren
Minister of Education
No.37 Damucang Hutong,
Xidan, Beijing, P.R.C
100816

He Guoqiang
National Bureau of Corruption Prevention of China
NO.2 Guang'An Men Nan Jie,
Xuanwu Disrict,
Beijing 100053