Ultra 4 on Safe mode, No Volume exist

Hi Team,

I'm using a Ultra 4 Readynas on OS 6.10

4x2TB drives

I recently have a power outage at my home and all of a sudden my NAS boots on safe mode. Its boots okay, goes to checking FS then goe's to safe mode.

I can access via HTTP but only using a default admin and password

Once I'm on the GUI , error says "No volume exist " on all 4 drives. There's important files I wasnt able to backup, therefore I'm here looking for some answers if my data is still salvable.

What I made so far none fixed it:

-  Reboot

- Shutdown, Remount the 4 Drives on same location and boot again

- Reinstalled OS via OS reinstall boot.

- Raidar can see the drives all healthy

I'm looking for answers If I can still salvage my data? I read similar threads but none really give detail what was the fix

- possible issue could be root or Filesystem corruption

Some of the forums suggest to go to tech-support boot mode , access the drives and do a backup of the important data on external drives and factory restart?

- I can send logs

I've never tried backing up  data on techsupport mode before therefore if someone can lead me how I can start would be appreciated.

- i can factory reset it but would like to backup some of the important files before doing it.

this is the closest thread my issue

https://community.netgear.com/t5/New-ReadyNAS-Users-General/Corrupted-dev-md0-in-OS6-10-2-ReadyNAS-Ultra-6-starts-in-safe/m-p/1826271#M38813

Netgear support Paid support won't probably assist as my machine is EOS/EOL with unsupported OS

Thanks Guys!