Text files changed back to different prior saves twice after edit

Hey everyone,

Since just over 2 moths I'm using Windows 10 and something really weird happened the other day I've never seen before in any Windows version.

I have this txt file on my desktop plus a backup of it and I added some text in that file with Notepad, saved it and made a backup.
A week later when I opened the file the added text wasn't there (pc had been turned off and in sleep mode during that week). The file was back to the state before I saved it, just as the backup.
So I added the text again and added some extra text and saved it and made a backup. Then put my pc to sleep mode.
When I woke up my pc a few hours later and opened the file, the file was the way after the first time I added some text.

To clarify a bit more, if needed:
Original text was A. Edited text to AB and saved.
Opened file after week and text was A. Edited text to ABC and saved.
Opened file after few hours sleep mode and text was AB.
Same happened to backup file.

I'd like to know what happened here. I'm afraid it will happen again, also with other files. Anyone any ideas?

- - - Updated - - -

And I just checked the files. One is what I saved, the backup file is the older file again. So it happened again.

No one any thought on what is happening or am I being unclear?

I wouldn't even know what the files should be syncing with. I have just this pc and no phones, tablets, clouds or anything are connected to it.
And I couldn't find anything about syncing files. Just found something about syncing Windows settings, but I can't touch those, because there are no other devices to sync with.

Try searching the computer for the missing files. You may be saving them to a different location.

Ben

What missing files are you talking about?

The changes you made may have been saved to a file with the same name, but a different location, meaning that the updated files are still on your computer somewhere. I suggest you start File Explorer and search for all files with the same name or names as the ones with which you are having problems.

Ben

I did have the original files in a folder on a second hard drive and those have indeed the same names. I can't check if it was saved to those files anymore, bc they're overwritten by the other files when I moved them back to that folder.

So let's say Windows did save to those files, why does it randomly choose to save it first to the files at location A and later to the ones at location B and then later back to A again and then even do it with just one of the two files and not the other? It doesn't make sense.

If you are trying to save a document to the original location, always click "Save". If you use "Save as", the dialog box that opens may show a completely different folder.

Ben

That's not what's happening. I tested this. I made a test txt file in the original folder and copied it to Windows desktop, edited the contents of the files and saved using Save, Save As... and close the window and clicked Save when it asked if I wanted to save the changes (this is how I usually save it). The paths showed were always the right ones to the files I had opened.