Windows 10: Someone else's email info is in my login screen on my personal laptop

Hi, I have someone else's email address and some of their data saved on my laptop. I don't know this person but believe it is someone known to my ex partner. How has this happened and what can I do about it?

:)

 

User account info lost after changing login email






I recently changed my main Microsoft account login email and after doing so, all my 10 machines no longer show my name on the login screen (shows my email address twice) or in the Start menu (only shows the email address) and as you can see in the above screenshot, permissions no longer show as my login and email address.

Things I've done so far to try and correct it:

1. Change my account to local login, then back to my Microsoft login, which temporarily corrected it, but then after a few restarts, the info gets lost again
2. Manually added my name in Computer Management > System Tools > Local Users and Groups > Users... this fixed it, but again, only until a restart

Has anyone else experienced something like this and no of a way to correct it (and make it stick)?

 

Laptop with broken screen How much?

I would like suggestions and look in local stores. I dont wanna buy a laptop from someone online. Sorry. But could be a good idea if you asked him about the performance on older games. Gonna make a list ofall laptops people suggest me.

Remove the screen for space purpose here its small desk and if the screen is opened it will hide my 22 inches lcd

 

Lock vs Login screen screenshot

You can use your own image of any background and just go to settings/personalize/lock screen and click on browse as in the image below. It should make whatever picture you use as the Lock Screen