If your M.2 is an NVMe drive, you will not find it listed by name along side the other drives in your system because it is not a SATA device. It is a PCIe device and generally only visible by name as a configurable hardware device inside of the BIOS with RAID enabled. If you are using AHCI, you may find BIOS settings for it (like 2X or 4X mode) but not the device itself by name. Likewise, you generally don't see your other PCIe devices like WiFi, NIC or GPU enumerated and identified by name in the BIOS.
Wraith // X870E Master | 9950X | 4090 Suprim | 48GB DDR5-8000 | GF3 1650W | Triple 360 Loop | Hailea HC-500A || O11D XL EVO
Spectre // X670E Gene | 9950X | AORUS 9070 XT Elite | 32GB DDR5-8000 | RM1200x SHIFT | Dual 360 Loop || Antec C8
Meh! // Precision 7720 | BGA CPU Filth + MXM Quadro P5000 | 4K Display | $500 Grade A Refurb | Meh!