Unable to connect my watson API

Hi, I need someone’s help.
According to plugin’s guide,I successfully got my API URL, username, and password.
But After I inputed them into setup form,I saw these messages.
I couldn’t understand what was wrong.

These are the messages:

Unable to connect to Watson Assistant service. Click here for debug information.

WP_Error::__set_state(array(
‘errors’ =>
array (
‘http_request_failed’ =>
array (
0 => ‘cURL error 35: SSL connect error’,
),
),
‘error_data’ =>
array (
),
))