Sử dụng ngôn ngữ xamarin để test tự động phần mềm trên appcenter

Currently I am using xamarin to test a software running on HTC Android Phone 6.0.1. As for the numberpicker input, I have a problem, that is not working on the Set button to save the month. The ways I used to affect the set button: app.tap̣ (x => x.Id ("button1")); With button1 is the id of the Set nut app.tap (x => x.Text ("Set")); Set is the value of the button's text property app.TapCoordinates (230,400) with 230 and 400 are the x and y values of the Set button What should I do next? Thank you all for your comments