Excel VBA - setting scope of Named Range to Worksheet problem

This works, but the Named Range has a 'Workbook' scope, even though the range is qualified to ActiveSheet. I'm stuck because the macro recordser version uses RefersTo. This is simper.
How can I make it 'Worksheet' scope (using this syntax version, if possible) please?

Private Sub btnOk_Click()

    Dim strSourceRange As String
    Dim intOffsetColumns As Integer
    Dim wksActiveWorksheet As Worksheet
    
    Dim rngSourceRange As Range
    
    strSourceRange = Me.refSourceRange.Value
    Set wksActiveWorksheet = ActiveSheet
    
    Set rngSourceRange = wksActiveWorksheet.Range(strSourceRange)
    
    intOffsetColumns = Me.txtOffsetColumns
    
    iCol = 1
    For iRow = 1 To rngSourceRange.Rows.Count - 1

        strName = "TRAC_" + rngSourceRange.Cells(iRow, 1).Value
        rngSourceRange.Cells(iRow, 1).Offset(0, intOffsetColumns).Name = strName

    Next iRow

End Sub

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