If you are an account owner and wish to control the note locking delay, open the Settings-Security-User can save notes section and set the desired option. Then Save.
Available options:
Immediately: Note is instantly locked for edition and deletion.
12h: Note is locked for further edition and deletion after 12h.
24h: Note is locked for further edition and deletion after 24h.
48h: Note is locked for further edition and deletion after 48h.
72h: Note is locked for further edition and deletion after 72h.
Never: Note is never locked