You can check the permissions on your /home/ec2-user/.ssh
directory and `/home/ec2-user/.ssh/authorized_keys file. They should be something like this:
ec2-user@ec2-server:~/.ssh$ ls -la
total 24
drwx------ 2 ec2-user ec2-user 4096 Jan 31 00:39 .
drwx------ 5 root root 4096 Jan 31 21:59 ..
-rw------- 1 ec2-user ec2-user 731 Jan 31 20:39 authorized_keys
-r-------- 1 ec2-user ec2-user 3243 Jan 31 20:39 id_rsa
-r-------- 1 ec2-user ec2-user 731 Jan 31 20:39 id_rsa.pub
-rw------- 1 ec2-user ec2-user 1976 Jan 31 20:39 known_hosts
You can also try to deploy as a different user.