You noticed that this is different from:
So, your board cannot have been flashed correctly in the first place.
In addition, there are reports that this MCU has troubles with newer Debian OS versions. See this link, which so far seems unsolved. If it is related to your board, I cannot tell.
The only solution seems to be flashing the board under a different Linux OS. Once correctly flashed, it should work.
It is my understanding that a successfully flashed board should return something like:
/dev/serial/by-id/usb-Klipper_sam4e8e_00313753383436313139303139303535-if00
I do not own this or a similar board, so I cannot offer much more guidance.