Fix Javascript code

Need a javascript expert to fix some issues with javascript page and credit card orders. We have a JSP page which adds sales order in the database. But not all orders are getting added in the database. Some of the sales gives below mentioned error Execute::Connection is closed null. We have set the database connection timeout to 45 secs from the web server and we allow 40 connections at one go. Which we think should have solved the problem but still the JSP page is giving the error Execute::Connection is closed null. It is a Creditcard processing page which links to our payment processor to process the payment but don't think it should be taking longer than 45 seconds to get a response back from the payment processor gateway. Also we have a javascript error on the CC page then it hangs showing a blank screen to the customer. IIS and Resine server on windows system The budget is $50