For about a day now it have kept saying this message when i try to join a multiplayer server, and its for all servers.
Yesterday (6th of February 2020) i downloaded hack (Metro) from a usb i have. I only did it for singleplayer, and when i started the Metro version up, i when in to my singleplayer world, and its was another world i spawned in, and i know this because, i had saved the Coordinates of my home, and tried to tp there, and i went it the middle of the ocean.
I then deleted the Metro version, deleted all my Minecraft files the (.minecraft folder) deleted the Minecraft Launcher through Control panel, re-installed Minecraft, and it still says "Failed to log in: The authentication server are currently down for maintenance".
I have read multiple articles, run all sorts of troubleshoots on my computer to see if there was any errors and there is absolutely non.

What do i do? 

--------   Update -------

I completely rebooted/restored my computer, and it works again.
And again, I read multiple articles etc. and didnt find ant solution, so if any of you have the same problem, just reboot your computer (takes around 2-3 hours) and you should be good