Revalidation of decree

Hello My father expired leaving behind property, we had decree in our mothers name three years ago , Now my brother is applying for home renovation loan along with mother.Problem is we did not register the name of my mother at registrar office .So wr went to register it now , but they are saying you have to get it registered within three months from the date of decree now property cannot be registered.The lawyers told me we need to get a new decree .Is there any other solution.We liveand property is in Gurgaon Haryana Please help