In Android Studio I added Image Asset to res folder. Icon Type is Notification Icons. In AndroidManifest I added
<meta-data
android:name="com.google.firebase.messaging.default_notification_icon"
android:resource="@drawable/ic_stat_name" />
On phones my icon is showing up as expected. But on Garmin watch (mine is Venu Sq2) icon is not showing up, instead just default message bubble icon.
Some apps like Gmail, Instagram has their own icon showing up on my watch notification and some other app notifications are not being shown like my app.
How to fix it?
You can‘t. The app icons are hardcoded in the firmware of the watch, which means Garmin decides which apps get original icons and which use the generic ones.