Hey,
NIOS will release 10th, 12th class NIOS hall ticket 2020 for theory and practical exams in the month of June 2020. The NIOS 2020 admit card will be  released online on the nios.ac.in as per new exam date. The new date will be released by the authorities. So, stay tuned with the official website of NIOS.
For detailed information follow the link given below:
https://school.careers360.com/articles/nios-admit-card
Hope this helps.
Good luck.