I bought social security for many years in Sanshui District, Foshan, but I have never received a social security card. Why?

There are only two possibilities. First, you applied for a social security card yourself, but you didn't go to the social security bureau to get it. After you handed in the photo and a copy of your ID card, you successfully deducted the money from 20 yuan and went to the Social Security Bureau to get it 40 days later. It is invalid if it is not collected after expiration. Second, you didn't go to the social security bureau to apply for a social security card at all. Method: go and reissue it.