hello aspirant,.

Although any candidates taking Mathematics from NIOS boards are eligible for JEE mains, you will not be eligible for JEE mains examination in 2022, despite you taken up mathematics subject from NIOS Board. This is because every candidate can take JEE mains for 3 consecutive and JEE advance for 2 consecutive times from the year of passing class 12th and your attempt will be counted from 2019 and not from 2020 because you have passed class 12th in 2019. Thus this makes you in non-eligible for JEE Mains 2022.

Further, to know more information about JEE mains examination in detail, you can follow the below mentioned link to know more : https://engineering.careers360.com/articles/jee-main-2022

I hope that this will help.