Strix z370-i bios only sees one m.2 nvme drive?

[ejacksn9]

ASUS Strix Z370-i MB
I7 8700 CPU
16GB Corsair Vengence DDR4 RAM
Geforce GTX 1080 GPU
2X 512GB Samsung 970 PRO SSD
2X 2TB Seagate Firecuda 2.5" HD
Corsair SF600 PSU
NODE 202 Case

I can boot to the bios but cannot see both SSD's. I know they are installed correctly had that problem a few years back on another build. When I first went into the bios it did show one drive but now neither is howing up. I had planned to set these PCIe drives up in raid zero?

 

[bmockeg]

Idk how to fix it but RAID with nvme won't give any real world benefit due to how fast they already are.

 

[ejacksn9]

MERGED QUESTION
Question from ejacksn9 : "Bios only sees one m.2 SSD out of two but Windows finds both"

ASUS Strix Z370-i MB
I7 8700 CPU
16GB Corsair Vengence DDR4 RAM
Geforce GTX 1080 GPU
2X 512GB Samsung 970 PRO SSD
2X 2TB Seagate Firecuda 2.5" HD
Corsair SF600 PSU
NODE 202 Case

When I first booted up in the bios it saw 1 m.2 nvme ssd and I tried to follow some of the steps to set up raid 0 but could not. I went back and restored the bios to default. I then went ahead and installed Windows 10 on the one drive but Windows showed both of the nvme ssd's? How can the bios only see one and Windows sees both? I would prefer to have the raid drive for more single drive space.