Myntra.com — trousers

I ordered a formal trouser from myntra.com. My mom received the product at home and when i came home, i opened the package and checked it, the color of the trouser was different from the one seen in the product photo on myntra.com. I even ordered the size which i use regularly but the same size became too large for me. So, i thought of returning the product to myntra.com. So, i went to their website and selected the "return order" option and did all the formalities and in return payment option i choose, "phonepe" as the option. After selecting that, it directs me to a new page where it keeps loading for hours and nothing happens. As i'm unable to return the order, i have no choice left with exchanging the order.
Kindly help.