i open it befor the code, and after i reach the code, i went in the castel, serching for the it, and save. i dont have a save to go back before to open the chest. Now i need the code from the gard.
Yes, but I'm talking about the main quest. Have you been to the lost continent yet? If not, the guard will not tell you the code. Keep going on in the main quest. You can come back from the lost continent any time.