it doesnt use my nvidia 3090 GPU but use intel one

[kotran88]

why is it?
at first, I downloaded
https://github.com/NVlabs/instant-ngp/releases/download/continuous/Instant-NGP-for-RTX-3000-and-4000.zip
this file and run instant-ngp.exe
then I did
run below command
python scripts/colmap2nerf.py --video_in ./IMG_1816.MOV --video_fps 2 --run_colmap --aabb_scale_16 --overwrite
it is okay but very very slow so I checked if it is using nvidia GPU but itsays 0% but intel basic graphic card says 100%

how can I use nvidia gpu to do work?