Minecraft multiplayer doesn't work what to do?

I saved over a month to buy Minecraft and then bought it. Then I wanted to play on a multiplayer server (Hypixel or GommeHD and something like that) but got the message: "Registration failed: The registration servers are currently shut down for maintenance." So I waited a few days hoping to finally be able to play on public servers. That was 3-4 weeks ago now and nothing has changed. I deactivated my firewall which didn't work. I'm completely desperate and have no idea what to do. I only want to be able to play on the servers for which I paid 25 euro. By the way, I bought Minecraft Java Edition for Windows 10 on the PC and that via the official Minecraft website.

Unfortunately I suspect that you bought the wrong version. Here I found an article that might help you further.

https://technik-hauptstadt.de/minecraft-windows-10-oder-java-wo-liegt-der-unterschied/2975/

What you need is the JAVA edition and not the Windows10 edition.

I bought the JAVA Edition on my Windows 10 PC everywhere it said it was the Java Edition

Did you also have a Microsoft account and added Minecraft there?

I'm sorry but I have no idea what you mean by "add"? I created a Microsoft account a long time ago and then signed in with it and bought Minecraft.

Then please read the Mojang FAQ once, it describes how to proceed.

I read this article through completely, but nothing was mentioned about how I should / can "add" Minecraft to my Microsoft account and I just noticed that I have not yet thanked you, of course, thank you very much for dealing with my problem

Grin… All right, no problem, but thanks. So, you have a Microsoft account and bought Minecraft through it? Then downloaded from there and installed? Logged into your Microsoft account from the launcher and started the game?

You have to be logged into your Microsoft account to play Minecraft Multiplayer. Parental controls may be active, see if something is activated. Is it your account or does it belong to someone else? You can only log into Minecraft as an account owner.

So much has my Google research so far.

That's exactly how I did it. It's my Microsoft account and will follow your two tips and hope it works.