Fix AWS SSM Connection Issue

I need help troubleshooting an AWS EC2 instance connection issue using Systems Manager (SSM). The instance is running Ubuntu and is not showing as online, despite having the SSM agent installed and attached to the AmazonEC2RoleforSSM.

Key Tasks:
• Diagnose and fix SSM connection issues
• Verify IAM role, instance profile, VPC, and security group settings
• Ensure necessary SSM agent and services are running
• Check if instance type or network configuration might be causing the problem

Ideal Skills and Experience:
• Proven experience with AWS SSM and EC2
• Strong understanding of IAM roles and VPC configurations
• Experience with troubleshooting on Ubuntu systems

Please only apply if you have relevant expertise.