Guideline 2.1 performance

Apple says they launched my app and loads a blank screen for iPhone OS 14.3

When I add my app to my iPhone and IPad, they work fine. I am not sure where I go from here. Is it something I am forgetting to do in Xcode? Or has anyone else had this issue? I am confused why it will come up on my devices but not once I archive for distribution.
Did you test (at least on simulator) with 14.3 ?

Have you an image in the launchScreen ?
If so, check it is not too large (should be less than 1MB).
I experienced problems with heavy images of serial MB.

Have you a way to test in TestFlight ?
Guideline 2.1 performance
 
 
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