Dial Locks require a three-number code in order to be unlocked, and if you have no way to know what the right combination is, you'll have to manually input numbers in hopes of opening the lock.

Try to open the lock. If that doesn't work, turn each dial down one click at a time, adding one number with each click. Try opening it again, until the lock opens.

How to activate the Time Lock Safe To open the Shelter Time Lock Safe in Blue Prince, you have to interact with the terminal so you can input the correct date and time for your run.