The authentication servers are currently not reachable Please try again I CANT PLAY ONLINE MULTIPLAYER?!!!

Hello I have just bought minecraft a few days ago and whenever I try to log on to any multiplayer game such as hypixel I get the error message "The authentication servers are currently not reachable Please try again."
 
I have logged in and out reinstalled minecraft tried different versions and nothing has worked. 
THIS IS ON MAC OS BTW
Can anyone help me?