You are going to encounter a music box (water harp) puzzle while exploring the Lost Temple of Yaesha in Remnant 2.
It requires you to play a particular tune by selecting the right notes. There is no way to solve this puzzle without finding some clues from your surroundings.
There are some weird symbols around the temple that are part of the music box puzzle in Remnant 2. Here is how you can decipher these symbols to open the way forward.
The Music Box puzzle solution in Remnant 2
You cannot straight away go for this music solution as you need to complete some other objectives around the temple in Remnant 2. Initially, you must travel to the Namless nest and defeat the boss there.
After defeating the boss, make your way toward the Faithless Thicket area and unlock the door that takes you toward the Lost Temple. However, first, you must restore the Water Harp’s power.

Make your way upstairs, and you will find a massive mechanism within a wall that contains a lever. You need to pull the lever to restore power to the Water Harp and unlock the entrance to another room.
Within the room, you will find a book containing different symbols. These symbols are the solution to the Music Puzzle in Remnant 2. Once you make your way to the music cylinder, you will find rows and four columns there. You are required to set all the rows according to the book symbols.

The most important thing to remember is that each line next to the symbol indicates skipping the row. So the solution of the Music Puzle is as follows.
Pin | ||||
Pin | ||||
Pin | ||||
Pin | ||||
Pin | ||||
With this, the mechanism will work, and you should pull the lever to raise the bridge. You can now make your way toward the Ravager’s Lair.