2 NVMe in BIOS RAID1 fail

Hi,
I’m not sure what I did, even though I’m used to mess up, this time … wasn’t me :wink:

I’ve 2x 2TB NVMe which I’ve been told to set as RAID1 in BIOS
I did, and while finishing the clean up (to make room for Qubes) I moved a bit of data to the RAID NVMe

Then I finished my clean up and went on installing Qubes, thinking it would use the entire (RAID) disk

But after playing a bit with Qubes (install and boot worked) I realized it didn’t overwright the data, they were still there ! But on one of the two disk only.

So I went on deleting it, and reinstalled Qubes … leading to now, no longer seeing the RAID NVMe available !

Either I did something wrong (Can’t think of anything)
Or the only reason why I could install Qubes was because of the foreign data “splitting” the RAID, and therefore my install was NOT on an actual RAID

Anyone experiencing this situation ?
Should I go back to my initial plan to have LVM accross 2x NVMe, or install some on one, and the remaining on the other ?
Or use soft RAID ?

What do you say ?

My main concern about LVM or soft RAID is for the backup/restore, will it work all the same ?