Not a web address. You only need to take your ID card and campus card to the communication service center next to the No.8 canteen of South School or the communication center next to the No.3 canteen of this headquarters to register your department and class. I will join the group in a month, and the cycle is a bit long. Just wait patiently.

You can call customer service 10086 to confirm. I just helped my classmate get it last week, and he has joined the group now.