The accessibility permission for the TheOneSpy app keeps turning itself off on the target Android device. Why does this happen?

Android's battery management system can automatically reset app permissions, including accessibility settings, especially on devices with aggressive battery optimization (such as Vivo). To prevent this, disable battery saver modes and configure the app to be excluded from battery optimization in the device's battery settings. You may also need to enable Autostart for the app. The exact steps vary by device manufacturer.