As I had seen in the cyber-intruder's system, they first managed to get a document containing confidential data from our bank. Your first action is to solve a specific letter they concealed. In your bag, there’s a duplicate letter I was referring to.

 

One letter will stand out as the key to your answer. Outside the Katara meeting room, you will find a waiting area where the hackers have left a clue. Make sure to get the right paper from your team before solving the puzzle. Compare both notes carefully. Stay patient and observant, and the solution will reveal itself. Good luck!