I was flying to Zurich today. Before the descent, I tried to change the arrival and suddenly, all the instruments and dials in the cockpit got frozen. But the aircraft still flies. This is the second time that I try this flight. After 1:30 in the first attempt, the same happened without changing anything.
I really don't know what's the cause. The outbound leg went perfectly well. However, the way back to ZRH is becoming impossible.