I am having the same issue.   I've tried many of the same fixes; none worked.  Spent the morning with QB help desk, in the end they said it was a problem with Word and MS 365 being "click to run" version.   Said I had to contact Microsoft to ask for a physical install of MS 365 instead of click-to-run.   Microsoft says there is no such thing as a physical install.  It's cloud-based, but the program is installed on my computer.   I really feel like I'm getting the run around from both sides.  No-one knows the solution.  Since others are having the same issue, I'd say QB needs to fix this... This is a serious problem!  It must be related to a recent update!