Not long into the game, Colt wants to head back to his apartment in Updaam to see if he can recall anything about what he's trying to accomplish.
Upon getting there and exploring the apartment, you'll notice a very obvious safe. But of course, the safe is locked by a four-digit code. Codes are generally found on notes and files throughout the game. Unfortunately, this safe can not be opened at this time. You need to progress through the story a bit more to do so.
When you have to head to Fristed Rock to find more information on the LPP, you must enter an Aeon Security shack on the pier. Inside, on a bit of parchment taped to the desk, you will find a code to your safe in Updaam.
Now you have the code. You can head back to your apartment and unlock the safe, however, due to the safe being part of the story, it is unmissable. According to Gamepur, even if you know the code before coming to Fristad Rock, the code will not work. You have to acquire the code to trigger the safe.
The code given to you is random. Even if you know someone else's safe code, it will not open the safe in your game.
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