logs : 


Flashing build_nrf54840dk to 1050266177
C:\WINDOWS\system32\cmd.exe /d /s /c "west flash -d c:\Users\J\Downloads\ncs-inter-main\l9\l9_e5\build_nrf54840dk --dev-id 1050266177"

-- west flash: rebuilding
[0/10] Performing build step for 'l9_e5'
ninja: no work to do.
[1/10] Performing build step for 'mcuboot'
ninja: no work to do.
[4/10] cmd.exe /C "cd /D C:\Users\J\Downloads\ncs-inter-main\l9\l9_e5\build_nrf54840dk\_sysbuild && C:\ncs\toolchains\0b393f9e1b\opt\bin\cmake.exe -E true"
[6/9] No install step for 'mcuboot'
[7/9] Completed 'mcuboot'
[8/9] cmd.exe /C "cd /D C:\Users\J\Downloads\ncs-inter-main\l9\l9_e5\build_nrf54840dk\_sysbuild && C:\ncs\toolchains\0b393f9e1b\opt\bin\cmake.exe -E true"
-- west flash: using runner nrfutil
-- runners.nrfutil: reset after flashing requested
-- runners.nrfutil: Flashing file: C:\Users\J\Downloads\ncs-inter-main\l9\l9_e5\build_nrf54840dk\merged.hex
error: unexpected argument '--x-ext-mem-config-file' found

tip: a similar argument exists: '--x-qspi-config-file'

Usage: nrfutil device <--json|--json-pretty|--skip-overhead> <--json|--json-pretty> <--x-qspi-config-file <PATH>>

For more information, try '--help'.
-- runners.nrfutil: Board with serial number 1050266177 flashed successfully.
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