Bhai aap 2020 ka exam fee paid nhi karna aapko 2921 me dena ho to aap 2021 ka exam fee paid karna .yah (nov-dec 2020) me uma hota hai.

Your NIOS admission is valid for 5 years. Once it is registered, the validity of 5 years is for both secondary and senior secondary. You can attempt to appear for the exams in these 5 years as many as 9 times. So you can appear for the exams any time within 5 years from the time you have registered with NIOS. At that point in time, you only will have to pay the exam fees.