If you want to sue the courier cos the you got have good cash supply, lots of time and lots of patience and a good lawyer.
A much cheaper and easier solution will be to bear the loss of 3200/- and send the buyer a new pair of shades. You will live peacefully and much longer.
This has not happened for the first time and neither this will be last time the courier cos damages a product so what's the point in taking them to court and getting 5000/- compensation after 5 yrs.
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