How to get a full Log from savscan?

1.
What is working fine...
savscan to Terminal screen works on this usb stick:

sudo savscan /media/user/usb_4GB_F32 -ns

Command line qualifiers are: -ns
-ns not silent ( list files scanned)
-s [*] : Run silently (do not list files scanned)

Part2.
Terminal screen includes files like:
/media/user/usb_4GB_F32/Manuals/2016Help.pdf
/media/user/usb_4GB_F32/Manuals/2020Help.pdf

...

3.
sudo savscan /media/user/usb_4GB_F32 -ns | tee /home/user/Sophos_scan.txt

Terminal screen works by displaying files in Part2. above.
But Log
/home/user/Sophos_scan.txt
is missing files in Part2. above
How come?

4.
tee command is not working as expected
How come?

5.
using Linux Ubuntu 20.04.3

6.
savscan --version
SAVScan virus detection utility
Copyright (c) 1989-2021 Sophos Limited. All rights reserved.
Product version : 5.85.0
Engine version : 3.83.1
Virus data version : 5.88
User interface version : 2.03.083
Platform : Linux/AMD64
Released : 26 October 2021
Total viruses (with IDEs) : 67461865

7.
Questions:
How to get a full Log from savscan?

Said differently,
How to get 'savscan' to output a full Log to a
- Text file /home/user/Sophos_scan.txt and simultaneously to a
- Terminal screen?

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