Reference Worksheet Named from User Input

Maybe like this :

ActiveCell.FormulaR1C1 = _
"=UPPER(TEXT(INDEX(Sheets(" & myValue & ")!C[-2],COUNTA(Sheets(" & myValue & ")!C[-2]),1),""mmmm d, yyyy""))"

and

ActiveChart.SeriesCollection(1).XValues = "=Sheets(" & myValue & ")!B2:B500"

Unfortunately it did not work. Any other thoughts? My full code is below:

Sub GenerateGraph()
'
' GenerateGraph Macro
'

 Dim myValue As Variant
 myValue = InputBox("Enter the Name of Client Return Stream", "Graph Name", "Client Graph")
  Range("I1").Value = myValue

ActiveSheet.Select
ActiveSheet.Name = myValue
Sheets.Add
         Cells.Select
    With Selection.Font
        .Name = "Calibri"
        .Size = 14
        .Strikethrough = False
        .Superscript = False
        .Subscript = False
        .OutlineFont = False
        .Shadow = False
        .Underline = xlUnderlineStyleNone
        .ThemeColor = xlThemeColorLight1
        .TintAndShade = 0
        .ThemeFont = xlThemeFontNone
    End With
    With Selection.Font
        .ThemeColor = xlThemeColorAccent1
        .TintAndShade = -0.249977111117893
    End With
    
    Range("A1").Value = myValue
    Range("A2").Select
    ActiveCell.FormulaR1C1 = "CUMULATIVE GROWTH OF CAPITAL SINCE INCEPTION"
    Range("A3").Select
    ActiveCell.FormulaR1C1 = "NET OF FEES AS OF:"
     Range("D3").Select
     ActiveCell.FormulaR1C1 = _
        "=UPPER(TEXT(INDEX(Sheets(" & myValue & ")!C[-2],COUNTA(Sheets(" & myValue & ")!C[-2]),1),""mmmm d, yyyy""))"
  
    
        Range("A5").Select
    ActiveSheet.Shapes.AddChart.Select
    ActiveChart.ChartType = xlLine

    ActiveChart.PlotArea.Select
    ActiveChart.SetSourceData Source:=Sheets(myValue). _
        Columns("I:N")

    ActiveChart.SeriesCollection(1).XValues = _
        "=sheets(" & myValue & ")!B2:B500"

    ActiveChart.ChartArea.Select
    ActiveSheet.Shapes("Chart 1").IncrementLeft -518.25
    ActiveSheet.Shapes("Chart 1").IncrementTop -131.25
    ActiveSheet.Shapes("Chart 1").ScaleWidth 1.5270833333, msoFalse, _
        msoScaleFromTopLeft
    ActiveSheet.Shapes("Chart 1").ScaleHeight 2.0347222222, msoFalse, _
        msoScaleFromTopLeft
    ActiveChart.PlotArea.Select
    Selection.Width = 428.388
    ActiveChart.ChartArea.Select
    ActiveSheet.Shapes("Chart 1").ScaleWidth 1.1664394338, msoFalse, _
        msoScaleFromTopLeft
    ActiveSheet.Shapes("Chart 1").ScaleHeight 1.1160409556, msoFalse, _
        msoScaleFromTopLeft
    ActiveSheet.Shapes("Chart 1").IncrementLeft -15.7499212598
    ActiveSheet.Shapes("Chart 1").IncrementTop -18.75
        ActiveSheet.ChartObjects("Chart 1").Activate
    ActiveSheet.Shapes("Chart 1").Height = 412.56
    ActiveSheet.Shapes("Chart 1").Width = 708.48
      Dim mySrs As Series
      Dim nPts As Long
      For Each mySrs In ActiveChart.SeriesCollection
      With mySrs
        nPts = .Points.Count
        mySrs.Points(nPts).ApplyDataLabels _
            Type:=xlDataLabelsShowValue, _
            AutoText:=True, LegendKey:=False
        mySrs.Points(nPts).DataLabel.Text = mySrs.Name
      End With
      Next


End Sub