How to fix incorrect detection of free disk space?

Question

FreeBSD

df -h gives the following:
Filesystem Size Used Avail Capacity Mounted on
/dev/ada1p1 94Gb 83Gb 3.4Gb 96% /usr
Previously, adequate information was given.
Recently it has been like this.
fsck tried to do both in single mode and in multiuser.
Finds errors but does not fix them.
How to run fsck so that it fixes errors? I tried to unmount the partitions in single mode and check if / failed to unmount naturally.

Answer 1

Boot from Live-CD and fix it.