ssh not working

Hi, there is a likelihood that you don't have your SSH Public Keys added to /home/<UserName>/.ssh/authorized_keys. You may attached the non working EBS to the working EC2, mount it to a folder, and update the /<MountedFolder>/home/<UserName>/.ssh/authorized_keys.

Replace <MountedFolder> with the folder on working EC2, and <UserName> with the login username of non working EC2.