Approach road

1. Our society is on the same survey number as the old one, recently the old society have got their conveyance deed done since then they are threatening is stating the approach road which passes through the old society and is the only access to enter and exit from our new society is their property according to the conveyance. To bring to your notice the recent sanctioned plan of our new society is of 2017 and it shows this approach road in it as the only road for access. Are we allowed to use the approach road? 2. Recently the Mahanagar Gas Pipeline installation work has started after 5 days for this work the old society has now raised an objection and is stating that we should have taken the permission and they want that the procedure should be followed. I being the secretary sent a request letter seeking permission for the respective contractor. The old society denied it. Can this work which is from a government body and which for the social benefit of more than 140 houses be blocked in such manner? For both the above queries, what should be done by us?