Why are there two social security cards?

Because social security has five risks: basic old-age insurance, basic medical insurance, maternity insurance, unemployment insurance and industrial injury insurance. Social security card refers to medical insurance card. Only when you have participated in basic medical insurance will you have a card. Generally, it will be distributed to employees within the next month or three months after joining the company.

If not, it may be that the unit only purchased basic old-age insurance (some units saved costs). Individuals can go to the local social security bureau to check whether they have purchased medical insurance with their personal ID cards, and if so, they can apply for a new medical insurance card.

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