backup error - no value given

i have other vm's without this error, so they are successfuly done with backup, but 3 vm's have this error

103: 2024-08-03 02:01:45 INFO: Starting Backup of VM 103 (qemu)
103: 2024-08-03 02:01:45 INFO: status = running
103: 2024-08-03 02:01:45 INFO: VM Name: h1
103: 2024-08-03 02:01:45 INFO: include disk 'scsi0' 'nfs-truenas:103/vm-103-disk-0.qcow2' 80G
103: 2024-08-03 02:01:45 INFO: include disk 'scsi1' 'nfs-truenas:103/vm-103-disk-1.qcow2' 2G
103: 2024-08-03 02:01:52 INFO: backup mode...

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