1/2 checks passed - Instance reachability check failed

Hello.

There are multiple reasons why an EC2 status check may fail, but the most common cause is a high CPU or memory load.
If you also check the EC2 system log, you may find that an error related to the cause is output.
https://docs.aws.amazon.com/AWSEC2/latest/UserGuide/instance-console.html#instance-console-console-output

Restarting EC2 may improve the issue, so please try restarting it.
There are other troubleshooting methods described in the following documents, so please try them.
https://docs.aws.amazon.com/AWSEC2/latest/UserGuide/TroubleshootingInstances.html