curl: (35) gnutls_handshake() failed: Public key signature verification has failed
<p>I have an issue, when Im doing curl request or git push, that show me </p>

<blockquote>
  <p>curl: (35) gnutls_handshake() failed: Public key signature verification has failed.</p>
</blockquote>

<p>curl --version</p>

<blockquote>
  <p>curl 7.50.1 (x86_64-pc-linux-gnu) libcurl/7.50.1 GnuTLS/3.5.3 zlib/1.2.8 libidn/1.33 libssh2/1.7.0 nghttp2/1.14.0 librtmp/2.3
  Protocols: dict file ftp ftps gopher http https imap imaps ldap ldaps pop3 pop3s rtmp rtsp scp sftp smb smbs smtp smtps telnet tftp 
  Features: AsynchDNS IDN IPv6 Largefile GSS-API Kerberos SPNEGO NTLM NTLM_WB SSL libz TLS-SRP HTTP2 UnixSockets</p>
</blockquote>

<p>I have already done: update and downgrade curl to version 7.38 but this do not help me.
Sorry for my English, tnx.</p>