The following packages have unmet dependencies:

[modem7]

Heya,

Just an FYI with the latest package:

sudo apt install ./proxmox-backup-client_2.4.4-1_arm64.deb
Reading package lists... Done
Building dependency tree... Done
Reading state information... Done
Note, selecting 'proxmox-backup-client' instead of './proxmox-backup-client_2.4.4-1_arm64.deb'
Some packages could not be installed. This may mean that you have
requested an impossible situation or if you are using the unstable
distribution that some required packages have not yet been created
or been moved out of Incoming.
The following information may help to resolve the situation:

The following packages have unmet dependencies:
 proxmox-backup-client : Depends: libssl1.1 (>= 1.1.0) but it is not installable
E: Unable to correct problems, you have held broken packages.

I have also attempted:

sudo dpkg -i ./proxmox-backup-client_2.4.4-1_arm64.deb
dpkg: warning: downgrading proxmox-backup-client from 3.0.4-1 to 2.4.4-1
(Reading database ... 145662 files and directories currently installed.)
Preparing to unpack .../proxmox-backup-client_2.4.4-1_arm64.deb ...
Unpacking proxmox-backup-client (2.4.4-1) over (3.0.4-1) ...
dpkg: dependency problems prevent configuration of proxmox-backup-client:
 proxmox-backup-client depends on libssl1.1 (>= 1.1.0); however:
  Package libssl1.1 is not installed.

dpkg: error processing package proxmox-backup-client (--install):
 dependency problems - leaving unconfigured
Processing triggers for man-db (2.10.2-1) ...
Errors were encountered while processing:
 proxmox-backup-client

[modem7]

Ignore. ID10T error.