User and root password randomly stopped working

The problem: So, I was using my CachyOS + KDE Plasma partition normally yesterday night, then, as usual, shut the computer down and went to sleep. When I woke up, I booted into my CachyOS partition, but I could not get into the system, as Plasma Login Manager would not accept my password. My password was not incorrect, and I did not change it the night before. I also did not update my system the day before (the last time I updated my system was on 17/02, or 4 days ago, as per the time I'm writing this post). I tried getting into TTY and logging in as root to change my user password, but I also got that the password was incorrect, even though it was not. Again, I did not change my root password the day before. When I clicked on the eye button on Plasma Login Manager, it showed me the password as I typed it, so the keyboard layout was correct.

The solution: I booted into a live USB stick, mounted into my CachyOS partition's root filesystem, then ran passwd and passwd <username> to reset both my root and regular user passwords.

This was fairly easy to solve, but still quite incovenient. I'm lucky I had my live USB stick with me. Does anyone have any idea as to why this happened?

(I feel like I must note that I was using multiple workspaces for the first time since I installed the system, though. Strangely enough, when I managed to finally log into my system, my workspace order was incorrect; what was Workspace 1 the night before became Workspace 2 today, and vice-versa. Could this have had anything to do with it?)