"watch-app" app is installed successfully but doesn't work on some devices

Hi:

I developed a "watch-app" app, it works for my vivoactive3 but not for fr255.
I've searched the history but finding nothing.

This is the first time I developed the "watch-app" in the app-store:

apps.garmin.com/.../f90196d0-3376-4561-87d7-b52f824e08f8

What's strange is that it works for my vivoactive3 as expected but not for
fr255. On simulator it works for both devices. On fr255 I downloaded it from
the app store and it succeeded to install, But I cannot find it on my fr255.
I've tried other apps and they all work. What's wrong? Do I miss something?

This is the project View class layout::

Class AppView

initialize
onLayout
onUpdate

This is the manifest info:

<iq:application entry="AppView" id="xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx" launcherIcon="@Drawables.LauncherIcon" minSdkVersion="1.2.0" name="@Strings.AppName" type="watch-app">

This the permissions info:

<iq:permissions/>

I heard that Garmin canceled "widget" app type so I selected "watch-app" to
implement my calendar app, Is it possible for the root cause? Can somebody shed
some light on it? Many thanks.