Allowed to put up temporary wall to divide living room of rented apartment in NJ

I just rented an apartment in jersey city. I was told my management that I am not allowed to make structural changes the apartment. But now I want to put up a temporary wall to divide living room and create another room. I plan to take down the wall after I move out. Someone told the management and they told they will cancel the lease if I do that. I have seen so many apartments in the same building who have dividers and no action has been taken against them. Some of them don't even have sprinklers in the rooms and some have way too many occupants. Am I legally allowed to put up a wall if I follow all the safety regulations. Can they kick me out if they have not taken an action against others. Someone told me that this was a new policy and any new tenant would have to follow it.