Xcode project not showing list of simulators

Question

I open my project in Xcode 6.1. When I try to run the project, the button is grayed out. When I try to go to Product > Clean, the option is grayed out. When

Answer 1

Deployment Target version change to a lower one helped for me:

Window -> Devices and Simulators -> Simulators. Check what are the latest versions of existing simulators.

Then go to your project's Target. Under Deployment Info, change Target to the version you saw the latest within your simulators. Mine was set to iOS 13.6 when the simulator was iOS 13.5 only.