Mesho online shopping app - Not deliverable area

I ordered a pair sandle of *** rupees. It was bigger in size. So I kept for exchange for smaller size. It accepted the request. After the date ended to return or exchange. A message pops up saying exchange approval denied because your area is undeliverable. Why ?? When you can order then why not take it again and give us what we want. That's what a online shopping platform is used for right. It's exchange. I didn't ask for refund. I ordered it on ** th july **** and I recieved the package on ** th july. Right on that day itself I put it for exchange. I have Goan through this * Times before also. But I kept quiet. But not again third time. Please take a necessary action against it. I either want my money or my size sandles.