If you want to simulate it immediately rather than taking care of the IDE issue generally, go to Tools -> Flutter -> Open iOS module in Xcode. But for a further solution, do a Flutter Clean, and remove the simulator from Xcode -> Window -> Devices and Simulators -> Simulators -> right click on your iOS simulator and click delete. Then add a new simulator from the bottom left corner “+” button in the same Devices and Simulators page you are on. Re run your app in flutter and it should be working.