Shenzhen social security can only be paid for two years.

You can make it up, but it will take two years at most, and it will be the last two years. More than two years can't make up for it. Need ID card, social security card, labor contract, copy of monthly salary table during supplementary period (with official seal), supplementary pension insurance application form.

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