Retaining a variable for 2nd or third execution of macro

[Ballarat]

I have created a slide which shows club photos and sponsors rolling along sides and bottom. and now want to use that slide to do a raffle draw. I have done it successfully with userform but its appearance on the slide is a bit clunky.
the basic process is
click on a text box -has a 0 displayed on the slide.
message box is displayed to enter start number
message box is displayed to enter the last number
textbox now shows winning number - from random generator
operator now clicks again for redraw if not claimed or for second or third prize.

in code below the second (or third time through) results in 1 as the number displayed not a new random generated number as Endvalue = 1. (On the userform I kept the EndValue in a another textbox that was hidden)
I would also want to set the displayed text back to 0 at the end or between the draw from 1st to subsequent other draws (I will add an End) command button could I do that then?)

Sub UpdateRandomNumber(oSh As Shape)
Dim X As Long
Dim EndValue As Integer
Dim StartValue As Integer
Dim Message, Title, Default
Dim MyValue As Integer
     ' Start Number
If oSh.TextFrame.TextRange.Text = "0" Then
   Message = "Enter Raffle Start Number"    ' Set prompt.
   Title = "Raffle Start Number"    ' Set title.
   Default = "1"    ' Set default.
   StartValue = InputBox(Message, Title, Default)
    ' End Number
   Message = "Enter Raffle End Number"    ' Set prompt.
   Title = "Raffle End Number"    ' Set title.
   Default = "12"    ' Set default.
   EndValue = InputBox(Message, Title, Default)
'  As a test Display dialog box at position 100, 100.
MyValue = InputBox(Message, Title, EndValue, 100, 100)
End If
X = EndValue  ' How do I get end value to = what was entered on ist time through?
oSh.TextFrame.TextRange.Text = CStr(Random(X))
SlideShowWindows(1).View.GotoSlide (SlideShowWindows(1).View.Slide.SlideIndex)
' Do it again as a test
SlideShowWindows(1).View.GotoSlide (SlideShowWindows(1).View.Slide.SlideIndex)
oSh.TextFrame.TextRange.Text = CStr(Random(X))
'Now force PPT to go to the slide again (ie, to redraw it) so that
'the changed text appears:
SlideShowWindows(1).View.GotoSlide (SlideShowWindows(1).View.Slide.SlideIndex)
End Sub
Function Random(High As Long) As Long
'Generates a random number less than or equal to
'the value passed in High
Randomize
Random = Int((High * Rnd) + 1)
End Function