Sometimes that happens to me. For me, it has something to do with the file syncing to the document library/Onedrive online where PQ is trying to pull it from. If I go in and open the document in the web app and everything syncs, I will make sure to save it and then it will make the changes in Power Query.
If you're importing it from a file on your hard drive, maybe consider connecting to the online location instead.
Good luck.
