Dear aspirant !

Hope you are doing well ! May be you are living in 2021 because this time jee mains will just happen twice ,not like previous year. Now come to your doubt , no it is not important to attempt both the attempts ,its your choice totally ,if you want to do so you can attempt . Your best percentile will be counted . However it is recommended to you to attempt both the papers to improve your rank and percentile .

Hope your all doubts has cleared now .

Hope it helps you !

Thanks