An object is printed layer by layer. To start a new layer or move to a new location the nozzle must travel on the top of a previous printed layer. This leaves visible marks on the top solid layers of your print. To solve this problem, check the following steps:
If too much plastic is extruded, every layer gets thicker than it should be. By changing the location of the nozzle, scars will occur on the last printed layer. To avoid scars on the top layer of your print, set down the extrusion multiplier.
One possibility to avoid scars on the top layers of your print is to lift the nozzle when changing location. This option allows a travel with your nozzle in an elevated state from one point of your object to another without scratching the previous printed layer. For choosing this option look at the screenshots below.