Compulsory off as weekly off- right or wrong ?

My Question is for the BPO industry working under SEZ, Pune. We get 2 consecutive weekly offs. May not necessarily be Saturday or Sunday. If a compulsory holiday is adjusted as Weekly off. Example # 15 August marked as Weekly off, can it be or should it be compensated as per law or employers can do that. We were told that since its a weekly off, we will not get any compensatory off or extra wages for that day. Please explain with the section and details which we can refer to and inform our HR team.