Why can't I see Android storage as a partition on PC?

I'm trying to recover an accidentally deleted video from Huawei P10. I use Ubuntu, so I tried to recover it using photorec. The problem is that I can't see the mobile's internal storage or SD card storage in the list:

PhotoRec is free software, and
comes with ABSOLUTELY NO WARRANTY.

Select a media (use Arrow keys, then press Enter):
>Disk /dev/sda - 2000 GB / 1863 GiB (RO) - ST2000DM006-2DM164
 Disk /dev/sdb - 240 GB / 223 GiB (RO) - KINGSTON SA400S37240G
 Disk /dev/sdc - 1000 GB / 931 GiB (RO) - WD My Passport 259F
 Disk /dev/sr1 - 3504 KB / 3422 KiB (RO) - Linux File-CD Gadget

The first row is an HDD, the second row is SSD, the third is an external HDD, and the last row is present only when the mobile is connected to the PC. The mobile is connected to the PC through a USB cable and I've set the Transfer files option. Same result with Transfer photos. Do you know what to do?