Autosave has a bug that needs fixing

[Charmi]

I open my Word files from within the Onedrive file directory where they are stored, I do not launch Word and then open the file. I am using Office 365. Nine times out of ten, autosave will be turned on but there have been times when it hasn't. When I switch on Autosave, I get a system message to say the file needs saving in Onedrive, (it is already in Onedrive), this message used to give me the usual option of filename and directory, now it doesn't. A few days ago, I spent 2 hours editing a file, and had to use the autosave procedure. I went back to the file yesterday and my 2 hours work had vanished. On closing the file a few days ago, I had not received a 'save' message. I looked at version history, my data wasn't there, so I spent another 2 hours re-editing the file. I was determined to work out what had happened, then I remembered that I had previously found a file in Onedrive/documents that should not have been there. So I checked Onedrive/Documents and there was my missing file.
Why does Autosave think a file is not in Onedrive when it is?
Why has the option to choose name and location been removed?