How can Shenzhen Longhua Foxconn pay social security without a social security card?

The social security card should be issued three months after you joined the company. I think your social security card should have been completed, but it has not been issued. You can check your social security card number in the social health center and try to return it only by card number.

Or tell the company's superiors that the social security card must be done.

It should be on it or at the assistant's.