Flipkart — Serial number not matching during return

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Flipkart

I've been a regular Flipkart customer and recently ordered a pair of puma shoes. There was a size issue so I tried returning it thrice but the serial number didn't match anytime. Tried contacting customer care but they literally don't help. They cut the call after putting on hold and misguided me. I was asked to wait and they said they sent a complain but instead I get a notif that my return was cancelled (this happened 3 times again). The return policy is valid only till 16 May and I'm stuck. My money is literally wasted and if no action is taken I'd never think of ordering from this app.