Hi Pooja, OC is an essential legal document that has to be obtained by the builder once the construction is complete. This ensures that the building has been constructed in a completely legal way adhering to the approved plan. Maybe there is some issue for which the builder has not got the OC yet.
There is no occupancy certificate for the project means that the building has not been given a “Pass Certificate” by the concerned authority. In short, it does not have all the mandatory infrastructure or necessary approvals that make the building inhabitable.