When checking out a customised Magento ecommerce website we are experiencing strange behaviour whereby during the last step (step 6 - order review) when Place order button is pressed sometime the website Empties the cart and goes into precheckout stage. The problem is intermittent.
We have integrated a 3rd party payment gateway which is working well. We are sure that this is a small bug which someone who is experience more than ourselves can identify it immediately.
We can give you full fpt access and other resources to debug and work on the project.