Configuration changes not saved after reboot or power off

I just installed OpenWrt on an x86 appliance (Protectli VP2420), all good but I have a weird behavior: I do changes with some of the interfaces, save and apply, but after a reboot all changes will be lost, any idea why this is happening? Thanks

Note: I have installed multiple OpenWrt devices (MT6000, X3000, Raspberry, Fusion VMs, etc.), therefore I have some experience with this, first time with this behavior

Try updating with squashfs-sysupgrade.bin via web interface. Maybe this will help.

I am using * ext4-combined-efi.img.gz This disk image uses a single read-write ext4 partition without a read-only squashfs root filesystem. As a result, the root partition can be expanded to fill a large drive (e.g. SSD/SATA/mSATA/SATA DOM/NVMe/etc). Features like Failsafe Mode or Factory Reset will not be available as they need a read-only squashfs partition in order to function. It has both the boot and root partitions and Master Boot Record (MBR) area with updated GRUB2.

I don’t know if I can apply that type of image?

Please describe in detail exactly how you installed OpenWrt on the VP2420. I see it has a M.2 SATA slot and on-board 16 GB eMMC, which one did you install OpenWrt on? Are you sure OpenWrt's file system is on internal storage and not something like a live USB?

I used this guide:

https://openwrt.org/docs/guide-user/installation/openwrt_x86#linux

I installed it in a 1TB SATA disk, I also followed the instructions on the guide to expand the root partition, now it is using all the 1TB. I can see it in LuCI.

The USB drive used for the installation has been removed

Are you able to write any files to disk when in normal operation?

touch ~/test.txt
reboot

Then, after the reboot

mount
ls ~/