v13 - outdated Data Mover service version found

[GabesVirtualWorld]

Homelab !
I switched from Veeam V12 to the new appliance V13. Backup of VMs is running fine, but one physical linux server I'm unable to backup, I get "outdated Data Mover service version found". It is a minimal Ubuntu Server install. Always on. When I add the server to Veeam, installation of all components works fine. The whole list, incl data mover service seems to get installed.

When I then create a new backup job and try to make the backup, I receive the "outdated Data Mover service version found" error.

So I tried to remove agents, uninstall everything, rescan, remove from configuration through the GUI of the windows client for v13 and then manually on the linux host I ran:
sudo apt-get remove veeam veeam-libs veeamsnap
sudo apt-get remove veeam veeam-libs blksnap

Then tried to add the server again by creating a new backup job:
"Managed by backup server"
"Individual computer"
"Backup volume level"
"add mount point /mnt/ftp"

And when I ran the job, it failed with:
9/13/2025 7:56:49 AM Failed : Processing xxxxx Error: Failed to generate certificate for xxxxx: host is managed by another backup server veeam

The old veeam server had the same name "veeam".

New attempt made a new protection group with this server, when it then does a rescan of the protection group it shows:
9/13/2025 8:15:46 AM Succeeded : Processing xxxxx
9/13/2025 8:16:00 AM Succeeded : Configuring Installer service
9/13/2025 8:16:00 AM Succeeded : Resolving server certificate
9/13/2025 8:16:00 AM Succeeded : Installing client certificates
9/13/2025 8:16:00 AM Succeeded : Restarting Installer service
9/13/2025 8:16:01 AM Succeeded : Connecting to Veeam Installer service on server
9/13/2025 8:16:02 AM Succeeded : xxxxx state updated
9/13/2025 8:16:09 AM Succeeded : [xx] Preparing OpenSSL3 package installation
9/13/2025 8:16:09 AM Succeeded : [xx] OpenSSL3 package has been installed
9/13/2025 8:16:19 AM Succeeded : [xx] Preparing Veeam Agent for Linux installation
9/13/2025 8:16:19 AM Succeeded : [xx] Package veeam_13.0.0.772_amd64.deb has been uploaded
9/13/2025 8:16:20 AM Succeeded : [xx] Package veeam-libs_13.0.0.772_amd64.deb has been uploaded
9/13/2025 8:16:20 AM Succeeded : [xx] Package blksnap_13.0.0.772_all.deb has been uploaded
9/13/2025 8:16:53 AM Succeeded : [x] Packages veeam_13.0.0.772_amd64.deb, veeam-libs_13.0.0.772_amd64.deb and blksnap_13.0.0.772_all.deb have been installed (0:00:33)
9/13/2025 8:16:53 AM Succeeded : [xx] DKMS package has been installed
9/13/2025 8:16:53 AM Succeeded : [xx] Linux kernel headers have been installed
9/13/2025 8:16:53 AM Succeeded : [xx] Veeam Agent for Linux has been installed
9/13/2025 8:17:02 AM Failed : Failed to send certificate, but certificate is required for remote agent management Error: Failed to generate certificate for xxxxxxx: host is managed by another backup server veeam
9/13/2025 8:17:03 AM Warning : This backup agent is managed by the Backup server veeam, ignoring control request from veeam
9/13/2025 8:17:03 AM Failed : Processing finished with errors at 9/13/2025 8:17:03 AM