Why do you receive pension messages before you reach retirement age?

Retirement is a matter within the scope of enterprise autonomy. It is this unit that signs a retirement contract with employees and leaves before the retirement age reaches. As for retirement procedures and retirement living expenses, the unit shall negotiate with retirees. After retirement, the unit continues to pay social security for it. Reach the retirement age stipulated by the state, go through formal retirement procedures, and the pension will be paid by social security. The two are different in nature. Retirement belongs to internal retirement. Theoretically, employees are still working, and the balance in their social security accounts continues to increase, but they just can't get in and out; And formal retirement, it is necessary to change the old-age insurance account that needs to be recorded into a pension account that can only be retired.