how to recover data when a .docx file closes on its own and reopens without having saved your work?

I'm typing in a .docx file when it suddenly closes; when it reopens the last 2 hours of input are not there. How recover the working draft??

I use

Microsoft Word for Mac, version 16.67 (Office 365, Volume license 2019). 

Preferences set to "Save Autorecover info," "save every 1 minute."

I have tried  https://learn.microsoft.com/en-us/office/troubleshoot/word/recover-lost-unsaved-corrupted-document, without success. 

@MicrosoftHelps and the website will not speak with me, saying my employer (the licensee) is contractually obliged to provide support. My employer's IT dept says contact Microsoft because they don't answer Microsoft questions. 

Thanks for tips.