Release Deed Cancelled After 2 Years without Notifying to Us

Dear Lawyers, This is Archana, my dad was passed away in road accident in Feb 2019. In my family, myself, mom and my grandma (mother of dad). My father owning some property hence we taken release deed from my grandma for no objection to transfer the property to me. Same release deed has been registered in-front of registrar. after two years, now my grandma in my uncle house (dad's brother). my grandma went to register office for cancelling the deed stating that "I am not educated, dont know what was written in the release deed" hence cancel the release deed like that. This was came to our attention, we showed our objection to register office that "Release Deed registered with in front of registrar post verbal confirmation." since all original documents of PATTA, Mother Documents with us. So we are objecting cancellation of the deed. But Registrar office, Cancelled the Deed without considering our Objection. This Apart, now Grandma is trying to register "Settlement Deed" of 1/3 of share in total property to my uncles (Dad's Brothers) Is this Possible? Since total property not yet portioned as 3. in this situation, is she able to register the Settlement Deed?