product in cart but when clicking on cart it shows empty
If you do a quick search of the issue queue for "Views results empty", you should turn up the solution: you've probably customized your shopping cart View to include a product relationship, but your test user must not have access to view all products. When Views goes to render the results and performs the access check on the View results, it won't show anything as a result.

If this is the case, my recommended solution would be to edit the View, open the advanced settings fields, and edit your query settings to disable SQL rewriting for the View.