From ₹10 to ₹482 in One Day! Why Do Option Premiums Explode on Expiry Day?

Sensex took a nosedive today, and the 76500 Put option skyrocketed over 400%! But why does this happen? What causes such insane moves on expiry day? https://preview.redd.it/bkhiq88fohie1.png?width=1200&format=png&auto=webp&s=0e61ef3076e038fe17f984a6840a560df790a571