I see I am not alone.  I have initiated so many tickets and sent so many emails to support@...  but haven't got any reply in one month.
What are alternative ways to contact them? Are there other email addresses?

What is their physical address?
I don't know in China but in the rest of the world, if a company exists (are they a real company?) they must be registered somewhere.
There should be a "register office" where you can access all their contact data, physical address, phone number, etc.