Myntra.com — Missing item in the package

I had received the package on 23 of June, the package was supposed to have 3 items, but it had only 2 items the trouser was missing worth 1472.29 RS, When I raised the complaint they told I would receive it by 25 of June. Which I didn't, so I called customer care again. They told they would investigate and resolve the issue. Now they are telling it was dispatched and delivered which I didn't. I demand a refund of the product which I didn't receive