If you also have this question: why wont my nintendo switch turn on?, then the reasons for it could be, either your power button is not working, the switch or power adapter is damaged or the battery has drained. So here are some ways to fix it:
Try to turn it on manually by pressing the Power button. Let it charge for some time. Check for the damage when you plug the charger directly into the Switch whether it fits properly or it's loose. Try to reset the AC adapter to potentially fix it. If your switch still remains unresponsive, then try to perform a hard reset.
