Error on AWS cloud9 IDE few days after ubuntu installation



I installed ubuntu on AWScloud9 IDE using SSH as the evironment type which was successful. But few days later I started seeing some errors.
I get series of errors when I open my cloud9 IDE. When I try to create a file from the cloud9 UI it says access denied, even connecting to EC2 instance through terminal also fails and displays permission denied (public key).
Please any help on the way out would be appreciated.