ssh 키를 입력했는데, 아마존 데이터베이스 서버에 접속이 되지 않아요.

The authenticity of host 'ec2-18-190-119-159.us-east-2.compute.amazonaws.com (18.190.119.159)' can't be established.

ECDSA key fingerprint is SHA256:YUdN7COo9JscaM4Gj/uaKZehD+mK1nK3HE8GKnRxujo.

Are you sure you want to continue connecting (yes/no)? yes

Warning: Permanently added 'ec2-18-190-119-159.us-east-2.compute.amazonaws.com,18.190.119.159' (ECDSA) to the list of known hosts.

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@         WARNING: UNPROTECTED PRIVATE KEY FILE!          @

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Permissions 0644 for 'react-nodebird.pem' are too open.

It is required that your private key files are NOT accessible by others.

This private key will be ignored.

Load key "react-nodebird.pem": bad permissions

ubuntu@ec2-18-190-119-159.us-east-2.compute.amazonaws.com: Permission denied (publickey).

➜  react-nodebird git:(master)

탄력적 ip 연결하고, pem key 디렉토리에서 ssh 키 입력후 yes 를 하였는데 아마존 db 센터에 접속이 되지 않고, 다시 git 명령어가 나오네요 왜 이럴까용 ㅜㅜ