Lenskart - Refused to replace glasses under warranty

I have been buying items from Lenskart but no document / receipt / Invoice was ever given to me on purchase.
I purchased these glasses around * months ago.. but no receipt was given for cash paid and no Warrenty card was issued to me.

When I asked them about Invoice / receipt, I was told that my phone number has been stored in their records and through which I can pull all the details of my purchase.

The recent glasses I purchased has cracked within just a few months. I am attaching a photograph.
When I asked them to replace the glasses under their warranty terms, they refused to change it.
Infact, they demanded Rs.****/- to replace the frame.

Even after multiple followups, they did nothing.
So I had to purchase a new frame from a local shop and paid heavily for the new glasses.

I need full refund and compensation for trouble caused.
They should be punished for their unfair trade practices for not issuing Invoice / warranty card to customer.