I presume you are using home assistant in a Proxmox VM?
If so, you need to make sure that the home assistant VM is shut down before starting.
You will need to create a second VM from which to mount the home assistant disk - I just use a generic ubuntu server image.
Note the ID of the HA and Ubuntu VMs in proxmox - for me this is 100 for HA, and 103 for Ubuntu.
The open a console to your Proxmox server, and edit the following file (substitute “103” for the number of your Ubuntu VM:
sudo nano /etc/pve/nodes/brain/qemu-server/103.conf
In the file, add a new line to allow you to access your HA disk (substitute the “100” for the ID of your HA VM). Use a free SCSI disk ID (I already have SCSI0, so went to 1):
scsi1: local-lvm:vm-100-disk-1
Save the file, and then boot the Ubuntu VM. SSH into the Ubuntu VM. If you type:
fdisk -l
You should see your HA disk and it’s partitions listed.
You can then follow the instructions at the top if this post to unsquash, edit and resquash the filesystem - for me the partitions are sdb3 and sdb5.
Once complete, remove the temporary files and shutdown the Ubuntu VM. Edit the Proxmox config file above to comment out the HA disk (not strictly necessary, but will prevent issues if you accidentally boot the VM whilst HA is running). Boot the HA VM, and you should be good.