Changing the Colour of an Auto Shape (Line)

Could anyone help me with this query. I simply want to create a line that changes colour, which I can do in part. But why when I run the code, when BLUE or GREEN is entered into Test Sub, it just runs as RED?

Sub TestShoot()
    Call DrawShooting(171#, 115.5, 255.75, 167.25, 2, "BLUE")
End Sub

Sub DrawShooting(StartX As Single, StartY As Single, EndX As Single, EndY As Single, _
Shots As Integer, Optional Color As String)
    Dim Shot As Shape
    Dim i As Integer
    Dim j As Integer
    
    'AddLine(BeginX As Single, BeginY As Single, EndX As Single, EndY As Single) As Shape - Member of Excel.Shapes
    If IsMissing(Color) Then
        Color = "RED"
    ElseIf Color <> "GREEN" Or Color <> "BLUE" Then
        Color = "RED"
    End If
    
    
    Select Case Color
        Case "RED"
            For i = 1 To Shots
            Set Shot = ActiveSheet.Shapes.AddLine(StartX, StartY, EndX, EndY)
                For j = 1 To 255
                    Shot.Line.ForeColor.RGB = RGB(255, 0 + j, 0 + j)
                    Application.Wait Now() + 0.0000007
                Next
                Shot.delete
            Next
        Case "GREEN"
            For i = 1 To Shots
            Set Shot = ActiveSheet.Shapes.AddLine(StartX, StartY, EndX, EndY)
                For j = 1 To 255
                    Shot.Line.ForeColor.RGB = RGB(0 + j, 255, 0 + j)
                    Application.Wait Now() + 0.0000007
                Next
                Shot.delete
            Next
        Case "BLUE"
            For i = 1 To Shots
            Set Shot = ActiveSheet.Shapes.AddLine(StartX, StartY, EndX, EndY)
                For j = 1 To 255
                    Shot.Line.ForeColor.RGB = RGB(0 + j, 0 + j, 255)
                    Application.Wait Now() + 0.0000007
                Next
                Shot.delete
            Next
    End Select
End Sub

It is obviously something to do with my "

If Color <> "GREEN" Or Color <> "BLUE" Then

" statement, but I'm not sure what. Also, is there a more intuitive way of selecting the colours than repeating similar code for RED GREEN AND BLUE. Any help is appreciated.