This file was originally an .stl. I converted from orphan mesh to 3D geometry using the 'create geometry from mesh' plugin. From this all entities left over from the orphan mesh were removed using automatic topology. These ones shown in the picture (plus a few more) are highlighted but not removed during this step. I wonder if perhaps there is another way to remove them since this does not work. [ignoring entities does not work either as it creates more than 50 child faces]
Much appreciate all advice! Thanks