DFU properly completed but Distribution phase changed to Failed


I made a DFU procedure with:

nRF52840 DK as Disrtibutor

nRF52840 Dongle as Target

Since composition data of my new firmware was the same of the one allocated on theTarget node, it remained correctly provisioned.

I also verified that new firmware was properly updated on Target

So, DFU was successfully completed, but at the end of the process these are the last messages sent by Distributor through serial communication:

Distribution phase changed to Applying Update
[17:22:01.676,086] <dbg> bt_mesh_dfu_cli: apply:
[17:22:01.676,086] <dbg> bt_mesh_blob_cli: blob_cli_broadcast: 1 targets
[17:22:01.982,879] <dbg> bt_mesh_dfu_cli: handle_status: 0 phase: 6, cur state: 4
[17:22:01.982,910] <dbg> bt_mesh_dfu_cli: handle_status: Target 0x001d receiving transfer
[17:22:10.910,430] <dbg> bt_mesh_blob_cli: retry_timeout: 5
[17:22:20.075,195] <dbg> bt_mesh_blob_cli: retry_timeout: 4
[17:22:29.234,588] <dbg> bt_mesh_blob_cli: retry_timeout: 3
[17:22:38.400,756] <dbg> bt_mesh_blob_cli: retry_timeout: 2
[17:22:47.553,466] <dbg> bt_mesh_blob_cli: retry_timeout: 1
[17:22:47.553,497] <dbg> bt_mesh_blob_cli: retry_timeout: Transfer timed out.
[17:22:47.553,497] <dbg> bt_mesh_blob_cli: drop_remaining_targets:
[17:22:47.553,527] <wrn> bt_mesh_blob_cli: Dropping 0x001d: 9
[17:22:47.553,527] <err> bt_mesh_dfu_cli: Target 0x001d failed: 3
[17:22:47.553,558] <dbg> bt_mesh_blob_cli: broadcast_complete: continuing
[17:22:47.553,588] <dbg> bt_mesh_dfu_cli: dfu_failed: 3
[17:22:47.553,588] <dbg> bt_mesh_dfd_srv: dfu_ended: reason: 3, phase: 3, apply: 1
Distribution phase changed to Failed

Why "Distribution phase changed to Failed" if I verified that DFU procedure was successfully completed?

Have I missed something?

Have I to ignore this message?

Please, let me know.