Yes, I know if I leave the fort magisters will attack me and become red on the map. But the problem was before I left the fort. Magisters which were yellow suddenly attacked me and the same situation was in the swamps after that. None of them wanted to talk

I don’t know what I did wrong but everything is OK now. I've loaded a savegame and killed Orivan first (it was commander Trippel last time). Dialogs are OK. Thx.