Hey yuka,
This thread is describing behavior I am also experiencing and am similarly puzzled by.
I just switched my docker to Directory from BTRFS because I figured it might be more stable, only for the issue to manifest less than 24h later.
At one point I got just short of 26 days uptime prior to it returning.
I also happened to replace my boot drive this past summer, so I think it's in ok shape?
Looking forward to hearing if you have any progress solving it. Best of luck!