Update NixOS then system broke. How to solve it?

TLDR: the error message is Kernel panic - not syncing: VFS: Unable to mount root fs on "fstab" or unknown-block(0,0) Long story: I ran the command nix flake upadte and then nh os switch --show-activation-logs --ask on my laptop then leave my home. Hours later I came back home, check the laptop and it was not responsive with black screen. I thought it is usual because my laptop sometimes cannot be woke up when sleep, so I long press the power button to turn it off then turn it on again. The l...