App closes after running appium test

I have create a test app, and here is my config

DesiredCapabilities cap = new DesiredCapabilities();
cap.SetCapability(“deviceName”, “samsung SM-G965F 9”);
cap.SetCapability(“UDID”, “2aedc7b9631c7ece”);
cap.SetCapability(“platformName”, “Android”);
cap.SetCapability(“platformVersion”, “9”);
cap.SetCapability(“appPackage”, “”);
cap.SetCapability(“appActivity”, “com.yy.iheima.MainActivity”);
cap.SetCapability(“noReset”, “true”);
cap.SetCapability(“launchTimeout”, “1800000”);

but after 10 or 20 seconds, this app auto close.
what is I missing ?
please help.

The “UDID” seems ios only. could you give some appium log?