CytronWiFiShield failed to make request to HTTPS endpoint

Hi,
I'm using CytronWiFiShield for my Arduino project and trying to run the https client example but failed.
Serial Output:
Start wifi connection
Connected to: ABC Unifi
IP address: 192.168.0.161
Connecting to api.github.com
Failed to connect to server.
Is there any extra step to do for https requests? (eg. cert)
Thanks
I'm using CytronWiFiShield for my Arduino project and trying to run the https client example but failed.
Serial Output:
Start wifi connection
Connected to: ABC Unifi
IP address: 192.168.0.161
Connecting to api.github.com
Failed to connect to server.
Is there any extra step to do for https requests? (eg. cert)
Thanks