what time does the exchange office in Narita for jr pass close?

The reason I'm asking is this we're going to arrive in Narita at 4:30 pm. I'm not so sure if I heard it right that the exchange office for jr pass close at 5:00 pm? I hope me and my daughter could make it on time so we can exchange and activate our jr pass ticket . So we would be able to use it for making a reservation using Narita express going to Tokyo station.