My sims game won’t start up

I installed the sims 4 on an external hard drive and completed the entire thing. Once I went to open sims 4 “verifying the sims 4 “ popped up along with a loading taskbar that moves very slow. Does anyone know the reasoning for this? Also, I have already uninstalled EA twice completely from my Mac and reinstalled it with the tool. Any tips or guidance will be appreciated !!