I know this is an old post, but I have the same problem, I don't know where I can include this code.
Support admins continue to respond with this link http://documentation.revive-adserver.com/display/DOCS/Invocation+code%3A+Zone+level#InvocationCode:ZoneLevel-Video but that guide don't tells anything... @a.hadi have you solved the problem? If yes, HOW? Thanks bro.