Swiggy — Biryani related

I ordered 10 biryani on swiggy but i received only 5 birayni and that too very small quantity, when i asked the customer care they are saying its a technical glitch regarding the cart and your order history is only 5 biryani .
they are refusing me for the refund for the other 5 biryani
actually the biraynis are on offer i get 319 rupees biryani at 39 and also now when i retry to order it was showing me 319 rupees
so for that i am asking refund for the remaining 5 biraynis those are not received and received only 5 out of 10 biryanis .i will attach the delivered pics and the ordering video in the below,
this was happened on[protected]