No data shown in simulator after restart Mac

Yesterday Xcode worked fine, after some time (I surfed on the internet) xcode had a problem and restarted itself. After reopening it, Xcode had a problem while building the app. So I restart my Mac, after that the app worked fine on the simulator, but all the data I stored in core data was gone. I there a way to rebuild the data?
No data shown in simulator after restart Mac
 
 
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