I had applied earlier for this drive it shows, not shortlisted. Now they are conducting drive again but I am unable to apply it stil shows not shortlisted which was for earlier drive

If you apply for any company but didnt get the interview call and your status is still applied this only means they may consider you for their upcoming drives. But if it is changed to Not Shortlisted, it means your score is not upto their requirement, and they dont even want you to consider for upcoming drive for the same role.
Note:- you can apply only once for a company for same role/profile. I hope its clear to you now.
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