Update app.py

app.py

@@ -1159,7 +1159,10 @@ with tab2:
                     del SimVar
                     del ref_dict, up_dict
                     del linenum_var1, UserPortfolio
-                    del up_array
+                    try:
+                        del up_array
+                    except:
+                        pass
                     del CleanPortfolio
                     del vec_projection_map
                     del vec_stdev_map