Myntra - Not exchanging the product

I ordered a compression sports shorts from Myntra on ** April **** and received the product on ** April ****. While ordering the app suggested me to get a size ** based on my previous purchases, so I complied. I also opted out of returning the product as doing so would cost me a little less and also because I had no intention of returning the product as I needed it. But the option of exchanging the product was still open. So I ordered it. But when I received the product it was too large for me. And so I decided to exchange it for a smaller size. But when I tried to do so, I wasn’t able to and a message kept on appearing saying that selected size was not serviceable at my location. Here, I’d like to mention that at the time of order no such message was shown that exchange would not be possible at the location I was ordering from. I was a bit perplexed by this and called their customer care who refused to exchange the product or provide any assistance and kept on saying that I should provide them with any other address or wait for another ** days. I ordered from my permanent address and don’t have any other addresses and by waiting for another month I’d run out of the exchange time and won’t be able to exchange the product at all. I even gave them an option that if there was no pickup available I was willing to courier it myself. But they refused for that also and said that there’s nothing they could do. Now I’m left with those oversized shorts which are too loose for me wondering how can these people be so pathetic.