Xcode emulator problem

Good morning to everyone. I have a big question with Xcode, to see if someone can help me, please. I explain: I am doing a view and I insert 3 buttons with their corresponding constraints. When I do a preview in xcode (using the editor settings), the view is perfect for me. But when I run it on an emulator for both iphone 8 or any other, the buttons are reduced or are out of place or do not appear ... and I do not understand what the problem is, due to the constraints and everything is perfect. Also, in the xcode when I select some iphone emulators I get 2 of the same type. For example, I get 2 from the iPhone SE (2nd generation), specifically I get iPhone SE (2nd generation) (040BBDPC-2F ....) and iPhone SE (2nd generation) (161B06F7-3DA ...),
Could someone help me or tell me something about this matter? I have had the project paralyzed almost 15 days ago. THANK YOU SO MUCH EVERYONE!!
You said:

and I do not understand what the problem is, due to the constraints and everything is perfect


How are you so sure ?
Did you test with other devices format to see what you get ?


I get 2 from the iPhone SE (2nd generation), specifically I get iPhone SE (2nd generation) (040BBDPC-2F ....) and iPhone SE (2nd generation) (161B06F7-3DA ...)


When you launch them, what do you see as complete description (including iOS version) ?
How did you install Xcode ?
If you need you can eliminate some simulators.
Can you elaborate a bit on which specific constraints you’ve added to these buttons, and how they’re constrained to each other and their parent view? Do you see any error messages in the Xcode console? Finally, if you inspect your hierarchy with the View Debugger, do you find anything unexpected?
Xcode emulator problem
 
 
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