barline not adjustable

I'm finding some problems with barlines when I layout out my score. At one point, I couldn't bracket the correct instruments by extending the bottom — it extended it too far no matter what I did — but got around that by selecting the first and last instrument and then selecting the bracket. HOWEVER, I still can't get the barline to stop at the vocalist's staves, or between their staves by dragging the bottom of the barline. There should not be a barline connecting Perc 2 to High Priestess, or between High Priestess and Queen.