If I have lost the copy of bank challan paid to NEET course given by nta( both printed copy and downloaded one) what should I do?

Dear Prabhu, am guessing you are talking about the challan you paid for NEET exam fees. If you have misplaced it, it is still fine. You are advised to keep it only for instances when you paid the fees and the amount was debited from your account but it doesn't show up against your application. But now because you have already attended the examination, it is ok not to have the challan with you. You will not be asked to show the challan during NEET counselling.