I run my program, the simulater showed the progress bar and suddenly disappeared and the pop up appeared and written there
Failed to initiate service connection to simulator
DTServiceHubClient failed to bless service hub for simulator iPhone 8 (81F102A0-7BDB-4A51-903B-CBC4AFFF93FB)
Just clean & build yor project it will run fine. If it does not help, then restart the xcode, clean & build the project.