Problem with using recordsortfields with CrViewer

[MadCatmk2]

Hi all

I currently have code which out puts the correct data onto a Crystal report viewed with the CRViewer control in vb6. I have one problem however. Once i have added the group in the second if statement i would like to sort the data based on the date of birth field. For some reason the code isn't working. The code is as follows

Private Sub Cadob1a()
Dim Report As New CRCaDob1a
CRViewer91.ReportSource = Report
SetReportLocation Report
Report.DiscardSavedData
Report.RecordSelectionFormula = RecordSelectionFormulaString
Report.GroupSelectionFormula = GroupSelectionFormulaString
Report.Text1.SetText ReportHeading
If ReportType = "'BySurname'" Or ReportType = "'CNT'" Or ReportType = "'PNT'" Or ReportType = "'Selected'" Then

msgbox "Surname Report"
    
End If
If ReportType = "'ByAge'" Or ReportType = "'Under5'" Or ReportType = "'5to74'" Or ReportType = "'Over75'" Then
    
    'This adds a group based on the current age formula.
    Report.AddGroup 0, Report.FormulaFields.Item(2), crGCAnyValue, crAscendingOrder
    
    Report.RecordSortFields.Add Report.Database.Tables.Item(1).Fields.Item(4), crAscendingOrder
    
End If
CRViewer91.ViewReport
Screen.MousePointer = vbDefault
Exit Sub
End Sub

I would appreciate any help in identifying whats wrong with the code i have. I know that the database table and field points tward the date of birth field and that this field is included in the report.

All help is much appreciated.

Thanks in advance