Description: critical Severity alert notification "StatusCheckFailed_System...".
It can indicate a hardware issue that may warrant a reboot. Most times the instance will no longer be existing on AWS as an automatic reboot will create a new instance with another ID to replace the existing one in the environment.
In general, to get more information about such alerts or further investigation, it is advised to open a ticket with AWS so that they can investigate it.
Credit: Isaac Ojeh