Hi,
Did your hosting changed something maybe ? Like the possibility to make outgoing connections from your server ? Or maybe they changed something with the cURL library (which is used to establish connections with external services like PayPal Pro) ?
Otherwise, what you can try to do is the change the code:
curl_setopt($session, CURLOPT_SSL_VERIFYPEER, false);
curl_setopt($session, CURLOPT_SSL_VERIFYHOST, false);
to:
curl_setopt($session, CURLOPT_SSL_VERIFYPEER, 1);
curl_setopt($session, CURLOPT_SSL_VERIFYHOST, 2);
in the file plugins/hikashoppayment/paypalpro/paypalpro.php and see if that helps.
If that doesn't, I guess you'll have to see that with your hosting company.