Computer says my password is wrong?

I stopped using my computer for a few months, and when I tried to log in again it says my password is wrong. I know for a fact it isn’t wrong because my other computer that is connected to the same Microsoft account logs in fine. It isn’t because my number lock/caps lock, as it still doesn’t work when I toggle them on and off. In addition, my wifi has changed so this computer is not connected and I am not able to connect it unless I can log in. It’s a pretty old computer but has worked fine for years. Any help would be appreciated :)