Hello

If your query is about NEET exam, to challenge the answer key candidates were required to pay a sum of Rs. 1000. After successful payment, candidates had to download/print the key challenge receipt.

Since it is late to answer this query, I hope your problem was solved. Do let us know if you have any other queries.

Good Luck!

Yes sir i understand your query regarding this as i would like to give you a brief about this through the official article of career 360link as follows:

https://www.google.com/amp/s/medicine.careers360.com/articles/neet-counselling/amp

If you still have any query ask me in comments