I changed my account password, but the system says that the password is incorrect for this account

I have a main Microsoft account, but recently I had a problem where the system wouldn't let me into my account and said my password was incorrect. I remember for sure that the password I entered was correct, and a few days later (today), I reset my old password and changed it to a new one. I wrote down the new password separately, then rewrote each character, but the system still says my password is incorrect!! I can't log in to my account using my phone, and I can't use the one-time code in the email either, because I don't have the button on my main account, but I do have it on this one. What should I do in this situation??