title: ssh problem caused by create another github account and add an new ssh
body: <p>I created a new github account, and therefore I need a new ssh key, but after set ssh key properly, i cannot push my project.
  After created a new ssh key, I added a config file in .ssh directory as following:</p>
  <pre><code># one(one@gmail.com)
  
  Host eric
  
  HostName github.com
  
  IdentityFile ~/.ssh/id_rsa
  
  User eric
  
  
  
  # two(two@ gmail.com)
  
  Host nuist
  
  HostName github.com
  
  IdentityFile ~/.ssh/github_id
  
  User nuist
  </code></pre>
  <p>and I run: ssh -T -v nuist, received following instructioins:</p>
  <pre><code>OpenSSH_8.3p1, OpenSSL 1.1.1g  21 Apr 2020
  debug1: Reading configuration data /c/Users/Leonard/.ssh/config
  debug1: /c/Users/Leonard/.ssh/config line 15: Applying options for nuist
  debug1: Reading configuration data /etc/ssh/ssh_config
  debug1: Connecting to github.com [192.30.255.112] port 22.
  debug1: Connection established.
  debug1: identity file /c/Users/Leonard/.ssh/github_id type 0
  debug1: identity file /c/Users/Leonard/.ssh/github_id-cert type -1
  debug1: Local version string SSH-2.0-OpenSSH_8.3
  debug1: Remote protocol version 2.0, remote software version babeld-0913e7e1
  debug1: no match: babeld-0913e7e1
  debug1: Authenticating to github.com:22 as 'nuist'
  debug1: SSH2_MSG_KEXINIT sent
  debug1: SSH2_MSG_KEXINIT received
  debug1: kex: algorithm: curve25519-sha256
  debug1: kex: host key algorithm: rsa-sha2-512
  debug1: kex: server-&gt;client cipher: chacha20-poly1305@openssh.com MAC: &lt;implicit&gt; compression: none
  debug1: kex: client-&gt;server cipher: chacha20-poly1305@openssh.com MAC: &lt;implicit&gt; compression: none
  debug1: expecting SSH2_MSG_KEX_ECDH_REPLY
  debug1: Server host key: ssh-rsa SHA256:nThbg6kXUpJWGl7E1IGOCspRomTxdCARLviKw6E5SY8
  debug1: Host 'github.com' is known and matches the RSA host key.
  debug1: Found key in /c/Users/Leonard/.ssh/known_hosts:1
  debug1: rekey out after 134217728 blocks
  debug1: SSH2_MSG_NEWKEYS sent
  debug1: expecting SSH2_MSG_NEWKEYS
  debug1: SSH2_MSG_NEWKEYS received
  debug1: rekey in after 134217728 blocks
  debug1: Will attempt key: /c/Users/Leonard/.ssh/github_id RSA SHA256:6phvZZlW2357l+xFxmE4xSuMr1EsOFm/owFL2gikjSU explicit agent
  debug1: SSH2_MSG_EXT_INFO received
  debug1: kex_input_ext_info: server-sig-algs=&lt;ssh-ed25519-cert-v01@openssh.com,ecdsa-sha2-nistp521-cert-v01@openssh.com,ecdsa-sha2-nistp384-cert-v01@openssh.com,ecdsa-sha2-nistp256-cert-v01@openssh.com,sk-ssh-ed25519-cert-v01@openssh.com,sk-ecdsa-sha2-nistp256-cert-v01@openssh.com,rsa-sha2-512-cert-v01@openssh.com,rsa-sha2-256-cert-v01@openssh.com,ssh-rsa-cert-v01@openssh.com,ssh-dss-cert-v01@openssh.com,sk-ssh-ed25519@openssh.com,sk-ecdsa-sha2-nistp256@openssh.com,ssh-ed25519,ecdsa-sha2-nistp521,ecdsa-sha2-nistp384,ecdsa-sha2-nistp256,rsa-sha2-512,rsa-sha2-256,ssh-rsa,ssh-dss&gt;
  debug1: SSH2_MSG_SERVICE_ACCEPT received
  debug1: Authentications that can continue: publickey
  debug1: Next authentication method: publickey
  debug1: Offering public key: /c/Users/Leonard/.ssh/github_id RSA SHA256:6phvZZlW2357l+xFxmE4xSuMr1EsOFm/owFL2gikjSU explicit agent
  debug1: Authentications that can continue: publickey
  debug1: No more authentication methods to try.
  nuist@github.com: Permission denied (publickey)
  </code></pre>
  <p>However, after run I: ssh -T git@github.com, it turned out successfully.</p>
  <p>I am guessing that the config file didn't work, but cannot be sure.</p>
  <p>I can't see where the problem is, and i had set the ssh in my github account likewise.</p>
  <p>Can anyone give a hand? I would really appreciate that.</p>