The root assembly conflicts with another assembly

Hi, after updating my Xamarin for Visual Studio it shows

Severity Code Description Project File Line Suppression State
Error The root assembly /Users/focus/Library/Caches/Xamarin/mtbs/builds/Sample.iOS/f4117d8ec82f837c5c099ce86166d4d3/bin/iPhoneSimulator/Debug/Sample.iOS.exe conflicts with another assembly (/Users/focus/Library/Caches/Xamarin/mtbs/builds/Sample.iOS/f4117d8ec82f837c5c099ce86166d4d3/bin/iPhoneSimulator/Debug/Sample.iOS.exe).

while building the ios project help me for solving this.
Thank you.