▶▶ Pod 153 - Report:

The machine lifeforms not only infected the YoRHa soldier units on the ground, they also infected the <Bunker> with a viral attack, activating a self-destruct sequence.

With this, the 13th Orbital Satellite Base <Bunker> was destroyed. 

2B and 9S avoided infection from the virus and escaped the Bunker before it was destroyed. 
Proposal: Find the remaining surviving YoRHa Soldiers and start another descent-to-ground operation on Earth to fulfill the mission.
I'm glad there were other allies
who were able to escape.
‫يسعدني أن هناك رفاق آخرون تمكنوا من الهرب.
Ein Glück, wir sind
doch nicht als Einzige entkommen!
Qué alivio. Otros lograron escapar.
Qué alivio. Otros lograron escapar.
Quel soulagement !
D’autres YoRHa ont pu s’enfuir !
Meno male!
Que bom! Mais aliados
conseguiram escapar.
Вот счастье-то!
Кто-то тоже успел спастись.