Smart Point Reliance - Overcharged

I went to reliance smart point new barrackpore (Bhorer Alo Mouza Aharampur, DAG no. *** ) I picked up one of snacks items name bhikharam chamdaml bhujia *kg price mentioned rs. *** however they charged me Rs. *** after that when I chacked my bill after payment I saw I was overcharged I immediately infomed to the cashier and manager name Mr. Sinha he haven't spoke to me anything he just said to his cashier ,tell the customer he have to pay *** rs otherwise leave the product. I felt so bad the way he treated the customers just a single apologize can solve out the issue but he was very pathetic and unprofessional , spoiling the brand name of reliance. I understand it can be human error but the way he(Store manager Sinha)showing his behaviour in front of me was spoiling the shopping experience.