Myntra - Wrong product delivered

I ordered * different man trunks underwear from Myntra in * order. They all got delivered in different time and the last I received * packs - * pack with * trunk and * pack with *. All * trunks were good and right except that last one which original pack was not sealed and the trunks inside were different colors from what I ordered and different size as well of both products - * was XL and another XXL size. I ordered all of L size originally. On the same day of delivery I made a complaint regarding this and in few days it was rejected saying that the delivery team checked the items before delivering them. This is not my first time that I buy the items from Myntra from last few years and few times I was making complaints that they delivered me wrong items. So I was surprised that they rejected this time because I don’t know how to prove in other way except pictures which I provided that the products were wrong.