Given:
Windows 10 Pro Latest
Windows App Driver Latest
Appium extension for Visual Studio 2019 Latest
WPF Application  
I have a simple WPF application that just has a combo box on it and I'm just trying to perform a simple test on it.  If I use FindElementByClassName method, it works. However, what if there are more than one combo box on the screen? I thought I could use .FindElementByName or .FindElementByAccessibilityId, but these do not work. (Regarding the latter) It does find the combo box element and clicks it but the items appear for a moment and then disappears.  
var comboNumber5 = session.FindElementByClassName(nameof(ComboBox));  //This works
vs
var comboNumber5 = session.FindElementByAccessibilityId("combo5"); //Does not work  
Code:
[TestMethod]
public void Combo5Test()
{
    var comboNumber5 = session.FindElementByClassName(nameof(ComboBox));
    comboNumber5.Click();
    var comboNumber5Items = comboNumber5.FindElementsByClassName(nameof(ListBoxItem));
    Assert.IsTrue(comboNumber5Items.Any());
    var lastItem = comboNumber5Items.Last();
    lastItem.Click();
    Assert.AreEqual(comboNumber5.Text, lastItem.Text);
}