Man pages matching name nvme-resv-register in section 1:

nvme-resv-register.1.en	debian 10 / nvme-cli
nvme-resv-register.1.en	debian 11 / nvme-cli
nvme-resv-register.1.en	debian 12 / nvme-cli
nvme-resv-register.1.en	debian 13 / nvme-cli