You could try restarting the car or resetting the infotainment system to see if that helps. If it persists, it may require a software update or service. Have you contacted Polestar support yet?
I had high hopes that the P3 would continue the P2's trend of physical controls. Unfortunately, it seems to be taking a step backward. I'm really worried about the potential reliance on the UI for basic functions like vent direction.