Debug and optimize ASP.NET C# page and code behind

I have an ASPX page that allows a customer to place an order. The page accepts in a product identifier and a service plan identifier as get variables. If those variables are not passed in, the page has defaults hard coded. The page looks up those two items in the database to retrieve their price and shipping weight. Which is then used to calculate the order information. The user can change the quantity and the page is updated accordingly using the free trial edition of Telerik's AJAX controls (available as a free download from [login to view URL]). When the user submits the page, everything is supposed to be checked for errors and saved in the database, but that doesn't happen. Can you please debug this page and get it working nicely? Please see the attachments for code sample and database design. Once we agree to work on the project together, I will send the full Visual Studio solution/projects and database. Note that the system creates the username/password stuff in a database / system outside of this one. You can ignore that part of the code for now. ## Deliverables 1) Complete and fully-functional working program(s) in executable form as well as complete source code of all work done. 2) Deliverables must be in ready-to-run condition, as follows (depending on the nature of the deliverables): a) For web sites or other server-side deliverables intended to only ever exist in one place in the Buyer's environment--Deliverables must be installed by the Seller in ready-to-run condition in the Buyer's environment. b) For all others including desktop software or software the buyer intends to distribute: A software installation package that will install the software in ready-to-run condition on the platform(s) specified in this bid request. 3) All deliverables will be considered "work made for hire" under U.S. Copyright law. Buyer will receive exclusive and complete copyrights to all work purchased. (No GPL, GNU, 3rd party components, etc. unless all copyright ramifications are explained AND AGREED TO by the buyer on the site per the coder's Seller Legal Agreement). ## Platform ASP.NET 3.5, LINQ, MS SQL