how to find the key for Chapter 6 in Chapter 1

[QAQ]

chapter 1 "INVESTIGATE THE RESTRICTED PART" I found all the letters and decrypted the gears, but I didn't finish the task. Why
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In Chapter 1, I completed all the other decryptions, but the quest "Investigate the Forbidden Zone" was still there, causing me to enter a sacrifice and not get the key for Chapter 1 to use in Chapter 6 vault
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在第一章节，我完成了其他所有的解密，但是“调查禁区”这个任务依旧在，导致我输入了牺牲，也无法得到第一章用于第六章保险库的钥匙

[Tanner (Amallah)]

I just tested Chapter 1 and everything works correctly. When you enter "SACRIFICE" the key spawns back at the checkpoint building. Make sure you enter "SACRIFICE" first, then go back behind the checkpoint building, locate and pick up the key, then go back to the cryptex and enter the correct word.

The "Investigate the Restricted Part" doesn't get crossed off until you're past the gate and finished Chapter 1, so it's not something you want crossed off before you get the key.