Why hasn’t the HK government closed the border between China and HK?

I don’t understand 

@joshuawongcf
Why has not the HK government closed the border between China and HK?

I do not understand

@joshuawongcf
20 yrs in Capital Mkts, Financial Svcs, wealth mgmt. Progressive Democrat #LearnMMT, Geraldine Ferraro VP campaign volunteer. Reside in NY14.
20 yrs in Capital Mkts, Financial Svcs, wealth mgmt. Progressive Democrat #LearnMMT, Geraldine Ferraro VP campaign volunteer. Reside in Ny14.