Note that NVMe devices are named by /dev/nvme[device number]n[namespace number]p[partition number].
This means if you format your NVMe device with at least one partition, you'll end up with at least three devices: /dev/nvme0, /dev/nvme0n1 and /dev/nvme0n1p1
Changing the title back to reflect the situation.
Note that NVMe devices are named by /dev/nvme[device number]n[namespace number]p[partition number].
This means if you format your NVMe device with at least one partition, you'll end up with at least three devices: /dev/nvme0, /dev/nvme0n1 and /dev/nvme0n1p1