This is worrying on many levels. So Microsoft force you to create an account to use Windows and then they reserve the right to block you from your own account, thereby potentially making you lose access to all your OWN data. This is crazy and yet another reason to stop using Windows as soon as possible.

That probably had nothing to do with LibreOffice. Lots of people have had their MS accounts locked for no reason. I guess the automatic abuse detection system just sucks.

My advice is don't use a MS account if you can, at least not for anything critical. You don't need it for development, you can use 3rd party CAs for signatures.