@Amit Chheda 💯 Agreed. You are spot on. There is every chance that the lottery system is also being misused because ultimately it's computer programming and nothing can be 100% foolproof.
Therefore, SEBi should definitely do forensic audit of lotter process being done, by deputing computer experts because IPOs have such huge amounts at stake.
Writing here is ok but real solution may come out if sufferers lodge complaint with SEBI on SCORES against particular registrars whom they feel are cheating. There is nothing to loose as you are already loosing your share of profit due to mischief of big fishes. Just take a step forward as present SEBI Chief is doing quite good work to regulate the share market.