The company won't buy me social security or sign a labor contract. What should I do?

You are an employee of a property management company, a property management company invited by the bank, an external employee, not a bank employee. Therefore, treatment insurance can only be discussed with the property company. Before joining the company, you should know whether the company has insurance. In real life, many units do not give overtime, but also force overtime. She doesn't care about the flow of people in your property management company, and there may be no technical content in her work, so whoever listens to it will use it. If you don't want to do it, you can defend your rights. Although you are an external employee of the bank, if you are exposed, the bank will negotiate with the property for fear of causing trouble, and compensate you for the insurance premium of several hundred yuan a month at most.

Further reading: How to buy insurance, which is good, and teach you how to avoid these "pits" of insurance.