Mask Tracking in Premiere Pro - Mask staying in frame after person leaves frame

I am working with mask tracking in Premiere Pro. When a person whose face is masked leaves the frame of the video shot, instead of disappearing the mask remains in the shot, hovering in the space where the person was last visible. Is there a setting in Premiere Pro that would automatically "tell" the mask to disappear when this occurs, and re-appear when / if the person re-enters the frame?

Or are we required to make a cut in the video clip, remove the mask when the person leaves the frame, and then re-add the mask to the clip if / when the person re-enters the frame?