Loss of Settings after reboot D Link DIR-600 (HW B2)

Hi All,
Another question. :slight_smile:
I have D Link DIR-600 (HW B2).
It was first flashed with openwrt-19.07.0-ramips-rt305x-dir-600-b1-squashfs-factory.bin and then after openwrt-19.07.0-ramips-rt305x-dir-600-b1-squashfs-sysupgrade.bin.
Everything works as expected until I reboot the router. For any reason if I reboot, all the settings are lost. And I must do everything from scratch.
Doubting on memory issue, I did check the memory. And there I don't see any issue...

root@OpenWrt:~# df -h
Filesystem                Size      Used Available Use% Mounted on
/dev/root                 3.0M      3.0M         0 100% /rom
tmpfs                    13.8M    280.0K     13.5M   2% /tmp
tmpfs                    13.8M     60.0K     13.7M   0% /tmp/root
overlayfs:/tmp/root      13.8M     60.0K     13.7M   0% /
tmpfs                   512.0K         0    512.0K   0% /dev

However, I do see that it uses temporary overlay area as it is not able to mount it.

root@OpenWrt:~# logread | grep jffs2
Mon Jan  6 16:47:23 2020 kern.notice kernel: [    0.000000] Kernel command line: console=ttyS0,57600 rootfstype=squashfs,jffs2
Mon Jan  6 16:47:23 2020 kern.info kernel: [    0.510900] jffs2: version 2.2 (NAND) (SUMMARY) (LZMA) (RTIME) (CMODE_PRIORITY) (c) 2001-2006 Red Hat, Inc.
Mon Jan  6 16:47:23 2020 user.notice kernel: [   12.527850] mount_root: jffs2 not ready yet, using temporary tmpfs overlay
Mon Jan  6 16:49:03 2020 kern.err kernel: [  130.776285] jffs2: Too few erase blocks (4)
**Mon Jan  6 16:49:03 2020 daemon.err mount_root: failed - mount -t jffs2 /dev/mtdblock6 /rom/overlay: Not a tty**
root@OpenWrt:~# logread | grep -i overlay
Mon Jan  6 16:47:23 2020 user.notice kernel: [   12.527850] mount_root: jffs2 not ready yet, **using temporary tmpfs overlay**
**Mon Jan  6 16:49:03 2020 daemon.err mount_root: failed - mount -t jffs2 /dev/mtdblock6 /rom/overlay: Not a tty**
root@OpenWrt:~#

Can you see why it is not able to mount overlay...

Thanks again !!!

https://openwrt.org/supported_devices/432_warning
https://openwrt.org/supported_devices/openwrt_on_432_devices