I have 20 pin SOIC part on the top layer of a two layer board. Pin 19 is N/C. Pin 18 is GND. I flooded the top layer of the board with a polygon connected to GND. It connects fine to pin 18 but inserts an odd bit of trace between pin 18 and 19, connected to 18 and almost touching 19. It's definitely part of the polygon. I can't get rid of it. If I move the polygon the extra bit stays in the same location as long as the polygon covers the area, then disappears when the polygon is no longer overlapping the part. I don't get a DRC error even though I should since the extra bit is too close to pin 19. I've tried deleting and redrawing the polygon - the extra bit comes back. Any suggestions? My board is ready to buy otherwise. Screen shot attached. I'm running 5.2.0.