Android Question UltimateWebView2 ClassNotFoundException

[aqsight12]

Caused by: java.lang.ClassNotFoundException: com.resikcemerlang.resikgo.android.ultimatewebview

I'm already checked the UltimateWebView2 on the library lists, and here is on how I initiate the ultimatewebview on the error part. Why it is still not detected my UltimateWebView2 library

Sub menu_explore_Click
Dim info As Panel = Sender
Dim data As MenuExploreType = info.Tag
Dim tag = data.name.ToLowerCase & " " & data.subname.ToLowerCase

Select tag
Case "kehadiran clock in / out"
LogColor("Info: Menu clock in / out dipilih",Colors.blue)
'menampilkan halaman presensi
Selection_Dot.RemoveView
Activity.RemoveAllViews
Activity.LoadLayout("lyClockInOut")
If Selection_Dot.IsInitialized = False Then
Selection_Dot.Initialize("Selection_Dot")
End If
Panel_Selection_Attr(Ico_Home)

'meminta ijin ke user terkait permissions
For Each permission As String In Array(Starter.rp.PERMISSION_CAMERA, Starter.rp.PERMISSION_ACCESS_FINE_LOCATION)
Starter.rp.CheckAndRequest(permission)
Wait For Activity_PermissionResult (permission As String, Result As Boolean)
If Result = False Then
ToastMessageShow("No permission!", True)
Return
End If
Next

' Inisialisasi UltimateWebView2
uwvClient.Initialize("UltimateWebViewClient1")
uwvClient.ImplementInWebView(UltimateWebView1)
uwvChrome.Initialize("UltimateWebChromeClient1")
uwvChrome.ImplementInWebView(UltimateWebView1)

' Inisialisasi JavascriptInterface
jsInterface.Initialize
UltimateWebView1.AddJavascriptInterface(jsInterface, "B4A")

' Setting WebView
UltimateWebView1.Settings.JavaScriptEnabled = True
UltimateWebView1.Settings.DomStorageEnabled = True
UltimateWebView1.Settings.DatabaseEnabled = True

sterrorpage=False
StartGetKoordinatGPSClockStamp