Flat transfer

The gift is worthless if the donee dies before accepting it since it is a bilateral transaction between two living people
As a result, the acceptance of the gift must be completed before the donor passes away or loses the capacity to make gifts. This was held in this Supreme Court judgment on the registered Gift Deed.
Legal heirs of Your Grandmother & Father (Based on the succession Certificate ) will own the Flat

What do you mean by "we adjudicated gift deed of my father and grandmother in 2016"? Please post the material facts.

Moreover, where is the flat situated? Is the apartment a registered Society? What is the law under which it is registered?