Problems with simulator

[Mark Smith]

I wonder if anyone has any suggestions I can try. I am using macOS 10.15.7 (Catalina), LC 9.6.3, Xcode 12.4 and iOS14.8

This configuration should be completely usable and indeed I am able to properly build an iOS app and install it on my 6S or 12 and it works fine. However, I can’t get it to run on the Simulator. I load the Simulator first, then press the Test button, LC saves the application, but it never gets past that point… no build happens, and nothing is loaded on the simulator. Subsequently pressing on Test does nothing. 

Just wondering if anyone might have a suggestion as how to fix this.

Thanks
Mark