Lilian:
If you are referring to the elevation origin (Project Zero vs. Sea Level), then select
just the text of the Level Dimension, open its settings, change from Measured Value to Custom Text, then select the desired Autotext from the Inset Autotext pop-up (to Project Zero, to 1st Reference Level, to 2nd Reference Level, to Sea Level). If that is not the problem, try posting some screen shots to better explain the issue.
David