Myntra.com — Return or exchange item

I have ordered 4 trousers from myntra and got it delivered today, i am unable to get exchange of these as i am having fitting issues .when i called customer care they are telling only 2 products get return what can i do with this fitting issue of other 2 products, super coins collection i am not aware how it was done i have not done it manually .i am requesting them with other size they are not doing it .its not at all good .need to take necessary action i dont need any super coins .