I was having no trobules with Ubuntu... until i enabled the option: "Automatic login"
When my computer turns on it show me the login screen (Should not 'cause i've enabled the automatic login option), well, i write my password and Ubuntu ask my password again in a infinite loop, when i try to turn off my pc Ubuntu says: "Another account is using this computer" and shows my user wich i'm trying to login... so what?
I don't kwno what to do, it's all i can describe here, i have not trying anithing, mi PC is new, Ubuntu is installed on a NVMe disk and i have a Nvidia 2060RTX