AutoCAD .NET :: Add Hatch Fill Polyline Area - No Error But Doesn't Show

I need to add a hatch fill polyline area but leave the text island out. What I did is put put Polyline ID and Text island ID into an ObjectIDCollection. The code doesn't throw any error but I can't see the hatch.

Public Function AutoCADAddHatch(ByRef newAddedHatch As Hatch, ByRef HatchElementIDs As ObjectIdCollection, ByVal HatchColour As Autodesk.AutoCAD.Colors.Color,
_ ByVal HatchLayerName As String, Optional ByVal PatternName As String = "SOLID", Optional ByRef strError As String = "") As Boolean
Dim db As Database = acApp.DocumentManager.MdiActiveDocument.Database

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