The message that arrived tomorrow

At 2:17 in the morning, Nia's dead radio said her name. The voice was hers, older and out of breath. It gave one warning: when the city goes dark tomorrow, do not let Malik open the blue door. Then the signal split. In one future, Malik was the reason everyone survived. In the other, he was never Malik at all. By sunrise, the blue door had appeared in her apartment. Malik was already knocking. Does Nia tell him the warning, or open the door alone?