Xcode Lagging Continuously - Force Quit Doesn't Work!!!

I have MacOs Mojave and enough available storage on my mac (40 GB Available), but every time I try to use Xcode it starts to lag. Even if I try to force quit, I just get an error message saying "Application not responding". Does anyone know how to fix this issue? Thanks.

I am able to force quit, but it still lags when I restart Xcode & even restart my Mac Pro.

Xcode Lagging Continuously - Force Quit Doesn't Work!!!
 
 
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