There us often a line just to check in for reservations, so they do not have time to answer the phone. Reservations must be booked months in advance, the only other option is to wait in an hour long line at opening each day.
I've never been there when it wasn't completely packed. I was able to wait for an hour one night for a table so you could try that. If it's a small party (1-2 ppl) you can put your name in to eat at the bar. Good luck.
Very popular restaurant. Try booking a few months ahead. Even then it is hard to get something between 5 an 730. Good luck. It's worth the wait.
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