First, see if you can start the car via the method in this video:
https://www.crestnissan.com/blog/2017/april/7/how-to-unlock-start-your-nissan-if-the-key-fob-battery-is-dead.htm
IF you can, you likely just have a dead battery.
https://www.youcanic.com/nissan/remote-keyfob-battery-replacement
If neither of these are working you will need to either provide more specific information like make/model of the Maxima, so someone here can tell you how to further troubleshoot, or you should take it to a local dealer.