My deleted Windows 11 account is messing up my current Windows 11 account!

Help! I need an expert Windows person to help me sort out my problem!

I was having problems with malware on my Lenovo laptop, so I created a new Windows 11 account. Then I deleted the old Windows account. The problem is this:

1. The old windows account does not exist.

2. I tried to "reclaim" my old account but it doesn't let me. I think someone else has taken that name.

3. My laptop computer's name is the OLD windows account name. It tries to connect to my old, deleted windows account. Since it can't (because it no longer exists, or because the name is now owned by someone else).

4. It doesn't properly save my data. Since it can't save it in the cloud it saves it in a download folder, but all the data is lumped together in one gigantic file, and all the data gets mixed up, and/or lost.

5. I have to continually reset up my desktop and reorganize my files. That's a real problem!

6. In order to fix the problem I believe I need to access the old Windows account and delete it, but I can't remember the password. I've tried guessing it, without success.

I could possibly create a brand new windows account, but I really don't want to do that. What are my options and which would be the easiest.

Please advise ASAP. Thank you,

Paul