Score - name for player - how to correct?

Hi,
In my score I’ve 3 percussion (timp, perc1,per2) fairly standard.
In the score on the second flow the name is the first instrument played not Perc 1 perc2
how to correct this?

In Layout Options → Staves and Systems → Staff Labels.

To the right, there’s a list of players and checkboxes for “show player name instead of instrument names”.