Do retirees need to pay social security when they return to the company?

When a retiree returns to the company, the company needs to buy social security for him. However, if retirees have reached retirement age, this part of the old-age insurance can no longer be purchased and paid. Enterprises only need to buy other types of insurance. If it is an internal retirement, it actually does not reach the retirement age stipulated by law, so you should buy full social security.