Can you see this button?
(If button doesn't work, restart your PC)

If button 'Notes' is not visible or you want to reposition it, open menu:

View > Toolbars > Customize...

Move button 'Notes' from left list to the right list.
Move Up. Move Up. Move Up.

In some cases, if button doesn't work, restart your PC.

Move button 'Notes' from left list to the right list.
Move Up. Move Up. Move Up. Click 'Close'.

In some cases, if button doesn't work, restart your PC.