Here's the full code fyi.
Dim ns As New NotesSession<br/>
Dim src As NotesDocument, db As NotesDatabase, view As NotesView<br/>
Set src = ns.DocumentContext<br/>
Set db = ns.CurrentDatabase<br/>
Set view = db.GetView("(CartItemsLookup)")<br/>
<br/>
Dim argsArray As Variant, arguments List As String, argName As String, argValue As String, idxEq As Integer<br/>
Dim SessionID As String, sess As String, docKey As String, itemdoc As NotesDocument<br/>
<br/>
argsArray = explode(src.Request_Content(0), "&")<br/>
SessionID = src.HTTP_Cookie(0)<br/>
sess = Strright(SessionId, "DominoECommerce=")<br/>
'sess = Strright(SessionId, "=")<br/>
<br/>
Forall arg In argsArray <br/>
idxEq = Instr(arg, "=")<br/>
If (idxEq > 0) Then<br/>
argName = Left(arg, idxEq - 1)<br/>
argValue = Mid(arg, idxEq + 1)<br/>
arguments(Lcase(argName)) = argValue<br/>
If Instr(argName,"Remove") = 0 Then <br/>
docKey = argName<br/>
Set itemdoc = view.GetDocumentByKey(sess & "~" & docKey)<br/>
If argValue = "0" Then<br/>
itemdoc.remove(False)<br/>
Else<br/>
itemdoc.Qty = argValue<br/>
Call itemdoc.ComputeWithForm(True, False) 'THIS LINE ADDED<br/>
Call itemdoc.save(True,True) <br/>
End If<br/>
Else<br/>
itemdoc.remove(False)<br/>
End If<br/>
End If <br/>
End Forall<br/>
<br/>
Print("[" & getDBRelativeURL() & "Cart?OpenForm]")