Xcode 10 iOS 12 iPhone Simulator haven't boot in each device

I update Xcode 10 iOS 12.0 in apple developer website the last few days.I download .zip unpackage to use.I want to use iPhone Simulator,but it's not work.All the time,it pause start up page screen.This Xcode isn't beta.Who can help me or tell me why?

iPhone XS Max -12.0

iPhone 8Plus-12.0