Wrogn - Return rejected due to quality check failed

I bought a wrogn slider from myntra.
The size did not fit so i tried to exchange it with a smaller size. But there was no smaller size available. So i had to return, by selecting quality not met. Since, there was no return option provided for size in return.The next day the agent came and took my sliders after checking. Following next day i received a message from myantra saying your return is rejected (Product dirty-quality check failed). The slider i handed over to the agent was clean and had no issue, therefore the agent accepted the product after inspection. However, the following next day they are saying the product was dirty?
And hence, my return got rejected, now i am left with as slider that makes my feet look like that of an dwarf. Thanks! myntra for terrible service.