Yellow Error "Frame for "MyApp" will be different at run time

Hi, I'm developing an app and after I change the app icon it's appear this error. Why? Previously I noticed, and it still does, that in the app settings it does not keep the LauncScreen.storyboard. In the drop-down menu it appears but as soon as I change screen it loses it. I don't know what to do.... Thanks!

Yellow Error "Frame for "MyApp" will be different at run time
 
 
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