My steering wheel won't go down. The button won't work either to make it go down.

Hello, The door lock actuators on these cars are notorious for failure. That is probably what you are experiencing, so that it where you should test first. Also, the actuator initiates power to accessories in the vehicle when the door is opened, but they are on a timer. When x amount of seconds pass, they turn back off until the door is closed and reopened. If it will not adjust with the key in the on position, that is more of a concern, and I would seek assistance in diagnostics after checking fuses. Don't be surprised if your technician recommends replacing all four door lock actuators plus the tailgate. A friend of mine is a master tech and factory trained at Infiniti, and sees these return several times over a few months as one after another fails. Test before you invest.