Can not change password of LUKS device with LUKS Header detached

[easycrypt]

Hello
I run the first time QubesOS with a detached header according to the instructions here on forum:

Install Qubes OS with boot partition and a detached LUKS header on USB

The purpose of having a detached LUKS header and boot partition on a separate external disk is to achieve a deniable encryption: Deniable encryption - Wikipedia The encrypted disk will look like an unused/empty unpartitioned disk. Boot into Qubes OS installer and on GUI screen switch to shell on another TTY by pressing Ctrl+Alt+F2. Assuming: /dev/sda - disk where you want to install Qubes OS /dev/sdb - USB disk where you want to install Qubes OS boot partition Find out the right disk name…

I would like to change the LUKS/FDE password, but it is not possible. Always the note appears: “No Luks device found”, regardless if I mount the external USB drive with the Header+boot partition or not. I tried also on CLI following instructions, like LuksDump etc, but when I choose the /dev/nvme01n (which has no p1, p2 etc) similar note appears.

Maybe somebody can help me to find the mistake
Bests regards

[DVM]

Everything is in the header, and based on your setup, it is separate from the disk where the encrypted data resides. This means that you have to both point to the encrypted disk and specify the header location with --header.