More info needed.
Is your battery charged?
You can do it with engine on park only running.
You must hold the switch on with out relishing it you will hear loud clicks and clacks,
don't let go of the switch, try to help the top relise by pushing the top with you hand is the midle front.
Check that you have oil in the reservoir it is under the spare tire, use Mercedes fluid only.
Regards.
aam.