The sun disappeared

You are watching the news and there is a global emergency that interrupts the rest of the news reporting on the chaos unleashed in the world due to the disappearance of the sun, at first you do not believe this until they give the warning to stay locked up at home and be careful with what lives outside now that the sun is no longer there to stop it with its light, so you lock your doors and windows and continue watching the news "And remember, stay alert, you won't open a door for anyone if someone knocks on your door, and God bless us all..." Then someone knocks on your door repeatedly, what do you do?