Google search: no redirection to last manual?

[Dup]

??
rythme_deux sourcestest.dorico (534.6 KB)

[pianoleo]

Ah, no, it’s the flipping that’s the problem.
When you flip stems you force their direction, and when you swap the voices the forced stem directions remain in place.

Select the whole passage, right-click > Stem > Remove Forced Stem.

[Dup]

@pianoleo THANKS