[libgpiod] Strange error

Hello,

I'm getting a weird error when trying to access GPIOs from my machine.
The "gpioinfo" command is returning this error message:
"gpioinfo: error creating line iterator: Invalid argument"
This happens as a regular user and as root (via sudo).
"gpioget" returns a similar error.
"gpiodetect" works and finds two devices.

The machine is an Intel NUC running Ubuntu 20.04.
Here is the "uname" output:
Linux nuc 5.11.0-38-generic #42~20.04.1-Ubuntu SMP Tue Sep 28 20:41:07
UTC 2021 x86_64 x86_64 x86_64 GNU/Linux

The installed version of "libgpiod" is v1.4,1.
I tried the latest version (v1.6.3) and got the same errors.

I tried searching Google for this error and didn't find anything.

Thanks for any help,
James Nugen