ssl - Cant get sometimes api.linkedin.com -

we have problem when trying curl -vvv 'https://api.linkedin.com/v1/' 5 request 4. problem subnetwork 109.72.148.0/22 . see firewall or block our request ?
example:

curl -vvv 'https://api.linkedin.com/v1/'

• about connect() api.linkedin.com port 443 (#0)
  
• trying 185.63.147.12... connected
  
• connected api.linkedin.com (185.63.147.12) port 443 (#0)
  
• initializing nss certpath: sql:/etc/pki/nssdb
  
• cafile: /etc/pki/tls/certs/ca-bundle.crt
  capath: none
  nss error -5990
  
• closing connection #0
  
• ssl connect error
  curl: (35) ssl connect error