It seems that the time difference between asking and answering questions is a little far. Ha ha. . .
However, there are still some informal companies in Beijing, not to mention pyramid schemes, and many of them do not pay insurance. These questions should be asked clearly during the interview. Sometimes it's normal to receive strange phone calls. For example, if you post information on the recruitment website and don't submit your resume, other companies can find you through search and will of course call you if they think you are suitable. Personal advice is to seize the opportunity as much as possible.