Outfitic - Package not delivered

I ordered a dress from Outfitic on ** September of Rs****. It was delivered in a week time.But then on **th september I asked for replacement and on **th of september I finalized the dresses I want to exchange with that old one.But for exchange I was asked to pay *** more because I was exchanging with * dresses of ****.On **nd September I paytm them the money and they told me after paytm they can dispatch.But my order was not dispatched. Then on *th of October I sent that old dress to the Mumbai office and I even sent them Courier reciept.And on ** October I again asked dispatched so they said yes and they said wait till ** October.I again messaged them on *nd November about it but they clearly messaged me that they are having Diwali Holidays till **th of November. And on **th november also I messaged them but they are not replying and now they blocked me from Whatsapp.