If you forget the passcode for a specific Space, you can reset it using your Master Passcode.
Click the Spaces icon in the left sidebar.
Choose Manage Spaces, then enter your Master Passcode.
Select the Space you wish to manage, then click the Edit button.
Click the Change Space Passcode button, then enter a new passcode for the Space.
Click the back arrow, then click the Save Updates button.
Learn More: https://manual.mylio.com/topic/manage-spaces