the classification you first showed was based on the image from 11.10.2017 with lots of clouds. You can try again with the cloud free image or change your training areas.
If you ran sen2cor to preprocess the scene make sure you include all resolutions: Sen2Cor-02.05.05-win64 - AttributeError: 'L2A_Tables' Object has no attribute '_L2A_Tile_PVI_File'