Not allowed for attending interview

Hi sir/madam Currently i'm working in psu (~ 1.5 yr. ) And applied for other psu in the training period. I got an interview letter from the Psu that i applied during the training, as soon as i know the interview date i applied for NOC in current Psu but for processing of NOC by current employer takes some time. So, as on the date of interview my NOC process is still going. I told the same thing to the PSU HR personal (to those are applied during training) but they had not allowed me to take interview without the NOC as i told that i will submit my NOC within a week ( even I was ready to sign. An undertaking for submission of noc within week otherwise my selection will be cancelled if i'm selected ) if i was allowed to attend an interview. But, they had not allowed me to attend an interview. After 2 days of interview date , i got my NOC from current employer, now as i got NOC , i tried to contact HR personal for rearrangement of interview if possible ( as interviews of my branch are still in process ) , but HR personal simply said "No " to me by citing that we can't do any thing now as you had not submit the NOC as on interview date. I feel very sad after that even after getting NOC, I was not allowed for interview. Is there any way that i can gave interview by law ?