Unabsorbed depriciation not adjusted in succeeding year

Dear members,

I had an unabsorbed depriciation in the A.Y 2011-12 , which my accountant missed while filling the subsequent year returns , having sufficient business income to adjust the unabsorbed depriciation.

This came to my attention while the return for AY 2014-15 was in process. when highlighted my accountant adjusted it in this return.

Please give your views on the correctness of the above situation. Whether my accountant is correct? If not then the remedy or consequences?