For some reason I can’t go on any server

When I go on a server for example hypixel it says Failed to login: The authentication servers are currently down for maintenance.

is it true that servers are down for maintenance or is that just a glitch or a bug because when I check how many people are on the server it has a lot of people on the server.

Please can you fix this issue because then I would have wasted money on this game if I’m not able to play anymore.