How to correct share certificate

First of all thanks everybody for giving me help on name on share certificate subject. I also take legal advise and they told the same thing that at the time of society formation if 2nd owner is present owner then his name should appear on front page. Now I purchased a flat in old panvel and Home loan procedure is going on from HDFC. I have one more query HDFC pointed out a mistake in share certificate that is scratch on backside of share certificate. Old society has mistakenly write first owner name on backside of share certificate and scratch it. HDFC want me to rectify this. Now new society is formed. How to correct this.