Builder sold garden flat but did not revise Plan what to do

In 2006, we purchased a garden flat. The sanctioned plan shows the current garden area as few scooter parking and cycle parking. However, on the agreement as well as on Index 2, the builder has mentioned selling of both the ground floor flat and the attached garden/parking area. On the conveyance deed, the builder attached old plan (not showing garden). The conveyance deed mentions that society members cannot access restricted areas which are mentioned on flat agreement. My queries are - 1) can the society try to claim our garden area in future? 2) was the builder required to revise the plan showing garden as part of the ground floor flat? 3) we plan to sell the flat, but the party is asking for revised plan since the loan bank requires the garden to be shown along with flat. What can be done regarding this?