very nice score !! but now I don´t hear an added Instrument

I finished a score of a string duo and it looks very nice.
I´m a professional classical orchestra musician and the picture of the score is the best I´ve ever saw from a computer program, because it´s possible and easily to read the real music in the score.

But there are so much bugs…

Now I want to add an third Instrument in the Duo score. It works in write modus, but I don´t hear it.
I set up the the new instrument in Halion, but Dorico ignores the set up of Halion.
After trying to hear it, the new instrument is not connected with Halion. Also after restarting dorico etc. etc.

The working flow in Dorico is much better than in Sibelius and look of the score too. But Dorico must work!
I give the chance and hope other people too, because for me as a musician it is important to read the music in the score and not only the ink of the printer.

Go to Play mode, and try Play/Apply Default Playback Template, or Play/Load Sounds for Unassigned Instruments.

Thanks, it works!