I have this table called tblLandAreas:

Level 1 = Bloq
Level 2 = Ships
Level 3 = Sides
Level 4 = Beds
Ship is a child of Bloq, Sides is a child of Ship and Bed is a child of Side.
And I need to show a report this way:

Only when _parentid is null
I have tried this but it is not working:

Try the following:
Output:
To project on your structure: