PEOPLE NEED HELP (HOLLOW KNIGHT)

Well, let's pretend that I wanted to get the MARK OF PRIDE amulet for 112%, but when I opened the chest I grabbed the amulet and went to the Queen of the Deer Roads Station, when I got to Dirtymouth I tried to equip it but it wasn't in the amulets menu. I already left the menu and went back in and nothing I also closed the game I would really appreciate it if you could help me please.