My INSERT Statements Works... 8/10 Times

I'm using the following code to add some data to a table:


Dim rand As Random = New Random


Dim num As Int32 = rand.Next(10000000)


Dim strConn as string = "......."


Dim sql as string = "INSERT INTO tblitemid (itemid, userid, datetime, supplier, comment, commenttype, uniqueid) VALUES ('" & label1.Text & "', '" & user.identity.name & "', '"& System.DateTime.Now & "','3763' ,'" & textbox1.text & "' , 'C' ,'" & num & "')"


Dim conn as New SQLConnection(strConn)


Dim Cmd as New SQLCommand(sql, conn)


Try


conn.Open()


Catch SQLExp as SQLException


Response.Write ("An SQL Server Error Occurred: " & e.toString())


Finally


cmd.ExecuteNonQuery


conn.Close()


End Try








As far as I can tell the code works fine. But for some odd reason I click the button, the code execute and the page closes as it should, but the data is never inserted into the database. I cant really seem to pick up on any paterns for why this would be happening. As a rough guess I'd say it doesnt insert the data 1 out of every 5 times or so it seems. Anyone every have any experience with this? Any comments would be helpful, cuz I'm at a loss.


If youd like to see more code let me know....


Thanks,


Scott