Editing Segmentation contained to one small region


I am trying to edit a segmentation in the segmentation editor. I am able to edit the segmentation to some extent, but any painting or drawing is only allowed in a small rectangle around the original segmentations. Any addition (say I wanted to draw something on the far left side of the image) does not work, has anyone encountered this before?

This section in the documentation should help: Segment editor — 3D Slicer documentation