Myntra.com — My return request is not being accepted. Ready to get the product verified from nike store

I placed a return request of nike casual shoes on myntra. My return got rejected stating that the product is used. They claimed that the product was delivered in an untampered box with proper quality check. But the box was slightly damaged from the top which clearly states that their claim is incorrect.
The product is unused, i have proper packing and box intact.
Adding few images of the product.
I have been contacting myntra customer care from past 4-5 days.
The product is not of few 100 rs that i wont mind keeping it.
I have genuinely not used the product and also i have fit issue that’s the reason i am fighting and struggling for the return.
Kindly assist me with the same.
I am ready to get the quality check done from nike store as well.