Instrument change not working/strange behaviour

I am doing the last finish of a brass quintet, where the performers are changing a lot of instruments/actions. All the instrument change works perfectly on all instruments, except for the Trp. 1. And I really can not figure out why this is.

This is how it is supposed to look (Trp. 2):

And this is where it won’t show correctly, on one combined stave:

I’ve checked all layout options - and they are all the same one each instrument. What am I missing?

Could you show us a bit in Galley View focussing on the Trumpet 1?

Have you added any extra staves to the trumpet staff? Dorico can’t handle instrument changes to/from instruments with additional staves.

@Richard_Lanyon Yes I’ve added extra staves - but also to the other instruments, which behaves very different. For some reason I managed to fix this problem by changing (only this instruments) layout options, even though all instruments have pretty much the same info and settings. But thank you for enlighten me on the topic. I realised, after some time, that exact thing.