On small town insurance in Shanghai! Urgent!

After helping you with the employment formalities, your labor manual will be handed in and the social security center will register for the record. If you can't find it online, you can go to the social security center in person. Ask the person in charge of personnel in your unit first, and ask which social security center in that district handles it, and then check. If you really don't pay it, you can go to the labor arbitration department and produce evidence, such as salary slips and time cards, which should be returned to you, and maybe even compensate you.