476013 Session bug in shopping cart

Hi to all programmer out there. Im urgently looking for programmer to fix 1 session bug in my ecommerce site which is a custom made php ecommerce. Some terms as below : Payment 100% escrow and will be release upon project completion that means upon testing completion on our site without any bugs or error. Work in live server. Full project details as per the file attached. Max can pay is USD 10 I guess its 1-2 hour job only. regards