Firebase – Android App Google AdMob "Ad failed to load : 3" with testID, "Ad failed to load : 1" for my GadID

I have the same code working on a whole new project, which can load the AdMob banner successfully with TestID or my Gad ID.
However, for a project that I was trying to move to Jetpack Compose, the same codes failed, with Test ID, "Ad failed to load : 3", with my Gad ID, "Ad failed to load : 1"

  <meta-data
            android:name="com.google.android.gms.ads.APPLICATION_ID"
            android:value="ca-app-pub-9528408865218303~2434754358"/>
.....
AndroidView(
                factory =  { context ->
                    AdView(context).apply{
                        setAdSize(AdSize.getCurrentOrientationAnchoredAdaptiveBannerAdSize(context,deviceCurrentWidth),)
                        adUnitId = unitId
                   
                    }
                },

it seems the codes works (at least for a whole new project), but there is some config/state incorrect in my old projects.

thanks