I had previously built without this problem but I lost the GraphicsSettings.asset and ProjectSettings.asset files (Image bellow). I think the problem is there because the game has not been modified, only these settings.
Which Unity version do you use? Also on which device does this happen? When you say that previously everything has worked, were you using the same device and same Unity version?
Hello, now I’m use Unity 2018.2.10f1. This happens on every devices I test.
When it worked before I used the 2017 version and the same devices but before works I had the same problem, even in the 2017 version.
What have you set in Player Settings → Resolution and Presentation → Aspect Ratio Mode? Do you specify aspect ratio in the manifest of your app? Does the issue disappear if you set Aspect Ratio Mode to Custom 2.1?
Well, I’ve tested it with a Native Aspect Ratio and Custom 2.1, nothing changes. The manifest you talk about is AndroidManifest.xml? If it is, it is not specified there.