If you are running OMV6 then this is normal because systemd-networkd is used for networking.
Yes, OMV6 on preinstalled debian bullseye i386(i686).
Great stack without the unnecessary doubled 2x x86 (x86-64) RAM access. Installed on the 4GB DoM of the NASBOX2 with only 40% occupancy on compressed BTRFS.
I think I'm off Synology 
Same to me, running Linux N2810PLUS 5.10.0-23-686-pae #1 SMP Debian 5.10.179-1 (2023-05-12) i686
I went back to the backup file "interfaces.bak" as "interfaces" in /etc/network. My "/interfaces.d" is an empty directory.
# This file describes the network interfaces available on your system
# and how to activate them. For more information, see interfaces(5).
source /etc/network/interfaces.d/*
# The loopback network interface
auto lo
iface lo inet loopback
# The primary network interface
allow-hotplug eno1
iface eno1 inet dhcp