I live in New York City. On May 10 I signed a lease for an apartment that is to begin on July 1 (a few miles from my current apartment). I have paid the deposit and first month's rent.
The new building/management company requires new tenants to confirm and schedule their move-in date. Two weeks ago I made several phone calls and left messages to do so; none of my messages were returned. On Monday of last week, I went to the management office to do it in person; the landlord's assistant told me that the apartment "probably won't be ready until July 4," because the current tenant is staying until June 30, and they need a few days to clean and prep the apartment for me.
I told her I'd have to try and make arrangements with my current landlord to stay four extra days, and that I'd get back to her about a move-in date. She said there was a chance I could move in a day earlier, on July 3.
I called the management company last Friday, and Monday and Tuesday of this week, to schedule my move-in and to confirm the date that the apartment will be ready. Again my messages were not returned. I went to the office again after work Tuesday, and the doorman called up, announced me, and they refused to see me and insisted that I call the number to schedule a move-in.
Because they refuse to let me confirm and schedule my move-in, what can I do to ensure that I can move in at some point around July 1? I need to prepare for this move and schedule movers now. I have a signed lease (for July 1), but I don't want to schedule movers, etc., just to show up at the building and be denied entry.

