Trust me. I have tried downgrade, upgrade. None of them works perfectly.
I did believe this stability issue came with later firmware releases (not the one when we first purchase the device).
And auto-update triggered such problem and only that time, we knew we got the issue.
For me, I wasted some days getting hands dirty with my own.
Below is my solved issue. Not 100% though. I still face connection loss for an hour sometimes. So I use FileZilla which I tuned to try file upload/download after a few minutes and it works for me now.
Good luck! People recommends Synology brand. But it’s way more expensive for home user.
https://community.wd.com/t/solved-wdmycloud-how-i-fix-intermittent-connection-issue/223414
