GitLab AWS AMI credentials

I have dumb question. I have installed GitLab AMI on AWS. I tried to login using root and Ubuntu as user id and it is is not letting me to login. Documentation says ubuntu@your-instance - what do i need to use for your-instance, Amazon instanceID, i-xxxxxxxx?

You need to enter your EC2 instance public ip.

For example, if your public IP is, then you can login with user ubuntu@
Also for root user use root@