Fitviewport Doesnt Scale Properly Libgdx

My problem is that my FitViewport where i keep my game world, scales in a way that in the X axis i can see black bars, but the Y axis seems to not mind the Gdx.graphics limits and

Solution 1:

The solution to this wasnt related to what i thought the problem was. The problem was that i was using wrong coordinate system and references to spawn enemies and bind the players movement. Now im using the gameViewport.getWorldHeight , and this solved my problem.