Developers are not necessarily system administrators.
Your hosting provider needs to check to confirm that connectivity between your site (the server it is on or the VPS/server itself) is good.
Could this be an issue with your hosting provider?  It isn't scheduled to go into effect until 06/2017 - but may be an issue currently.
https://www.paypal-knowledge.com/infocenter/index?page=content&id=FAQ1914
If you have shell access, you can confirm connection by the following command 
	
	
	
		Code:
	
	
		curl https://tlstest.paypal.com
	 
 You should see similar to this
PayPal_Connection_OK[15:24]
with the timestamp being different.
Are you using the internal functions or something like BD Paygates add-on?