To fix this problem, you need to run "Purge" on the model, and then update the drawing. The purge will delete this rogue element, and will no longer appear on the drawing.
To run purge only for the AS elements, you need to :
- open the purge dialog (type : purge)
- close it WITHOUT clicking on the purge all button. This will purge the Acad elements as well, which is not desired.
- when you click on "Close" and the dialog closes, the purge is executed.