ZFS error while mounting an encrypted partition

ZFS errors, I dont know why. Here are the step-by-step actions I took to attempt to mount the encrypted ZFS disk.

-shellsession
$ sudo zfs list

NAME                                               USED  AVAIL     REFER  MOUNTPOINT
bpool                                              322M  1.44G       96K  /boot
bpool/BOOT                                         320M  1.44G       96K  none
bpool/BOOT/ubuntu_uy913x                           320M  1.44G      320M  /boot
rpool                                             89.2G   802G      192K  /
rpool/ROOT                                        16.3G   802G      192K  none
rpool/ROOT/ubuntu_uy913x                          16.3G   802G     9.34G  /
rpool/ROOT/ubuntu_uy913x/srv                       192K   802G      192K  /srv 
rpool/ROOT/ubuntu_uy913x/usr                      3.85M   802G      192K  /usr 
rpool/ROOT/ubuntu_uy913x/usr/local                3.66M   802G     3.66M  /usr/local 
rpool/ROOT/ubuntu_uy913x/var                      6.92G   802G      192K  /var 
rpool/ROOT/ubuntu_uy913x/var/games                 192K   802G      192K  /var/games 
rpool/ROOT/ubuntu_uy913x/var/lib                  6.60G   802G     6.39G  /var/lib 
rpool/ROOT/ubuntu_uy913x/var/lib/AccountsService   244K   802G      244K  /var/lib/AccountsService 
rpool/ROOT/ubuntu_uy913x/var/lib/NetworkManager   1.46M   802G     1.46M  /var/lib/NetworkManager
rpool/ROOT/ubuntu_uy913x/var/lib/apt               120M   802G      120M  /var/lib/apt
rpool/ROOT/ubuntu_uy913x/var/lib/dpkg             89.7M   802G     89.7M  /var/lib/dpkg
rpool/ROOT/ubuntu_uy913x/var/log                   328M   802G      328M  /var/log
rpool/ROOT/ubuntu_uy913x/var/mail                  192K   802G      192K  /var/mail
rpool/ROOT/ubuntu_uy913x/var/snap                 5.57M   802G     5.57M  /var/snap
rpool/ROOT/ubuntu_uy913x/var/spool                 276K   802G      276K  /var/spool
rpool/ROOT/ubuntu_uy913x/var/www                   192K   802G      192K  /var/www
rpool/USERDATA                                    72.3G   802G      192K  /
rpool/USERDATA/edgard_7focix                      72.3G   802G     72.3G  /home/edgard
rpool/USERDATA/root_7focix                        1.56M   802G     1.56M  /root
rpool/keystore                                     518M   803G     63.4M  -

* After this one, I executed the command sudo zfs load-key -a, the output was

Key load error: Failed to open key material file: No such file or directory
    0 / 1 key(s) successfully loaded

* I tried to enter the key manually by this command

-shell
    sudo zfs load-key -L keylocation=rpool/keystore rpool

I got this output

Key load error: Invalid keylocation

* I executed this command to check different status

-shell
    sudo zfs get -Ho property,value encryptionroot,keystatus

output

keystatus	unavailable

It supposed to be **available** From now, I dont know where my-key-file is stored and how can I do to mount this **encryption disk**.