How to reset bar lines in single stave part

I have an arrangement for 5 players, using 7 instrumental lines. I have extracted three of these to a single part (two use five line clef, one uses a single line clef, it's a tambourine part at the end of the piece). I'm using Hide Empty Staves so that the 3 different instrumental lines appear as a single line throughout the part.

In the attached picture the bar lines only extend above the single line tambourine stave. I can't work out why, and can't fix. The next screenshot shows the other two parts not hidden (deselected Hide Empty Staves).

Any suggestions on how to make the single line appear normally?
TIA