Not able to decline the interview call neither confirm it

I was not able to confirm the interview call for webyog quality assurance but not whenever this drive happen again I am not able to apply again because it says you have already applied and neither do i get call letter because earlier I was called for interview then why not again. how can I reset this.

when future drive will be of same position then you will be accept or decline the call

there is future drive of webyog quaity assurance in delhi but i am not able to confirm or decline the interview offer in the interview only says last date to confirm is over

if it shortlist you the you will be able to decline or accept if there is better candidate than you, you have too wait