reServer Industrial J4012 Flash Error

Use a tool like gdisk or parted on Ubuntu to correct the GPT table. You can try the following:

sudo gdisk /dev/nvme0n1

Then, enter the command r to repair the GPT structure, followed by w to write the changes. Alternatively, using parted to check and correct alignment issues might help:

sudo parted /dev/nvme0n1 align-check optimal 1