Minecraft Mojang Mode? Does anyone know?

I recently got Minecraft Java Edition and bought it with a Microsoft account. The single player works, but the multiplayer. I always say "Please switch to mojang mode", someone knows what to do. I've already read forum posts but nothing that helps me.

I'm not aware that you can buy Java Edition from the Microsoft store

Oh, sorry, i didn't mean that i meant i bought minecraft java edition and had to own it either with a microsoft or mojang account since you can currently no longer create mojang accounts i took the microsoft account.

Nobody said that either. If you buy a Java account today you have to use a Microsoft account as there will be no more Mojang accounts.

I just always say when I try to play multiplayer please switch to mojang mode to play with your original account