@roykAfter many hours, what fixed my issue is reverting to an older kernel .
Indeed it seems 6.1.75-vendor-rk35xx might have issue with nvme / pcie and so the penthat
the solution that worked was downgrading to the 24.8.2 version of the kernel :
sudo apt install linux-dtb-vendor-rk35xx=24.8.2 linux-image-vendor-rk35xx=24.8.2
reboot
for reference the solution found was in this post
Inis got a reaction from royk in Radxa rock5c - PentaHat and EMMC