Cannot install jetson_multimedia_api after flashing with ./flash script

Hello,

sudo ./flash.sh jetson-nano-emmc mmcblk0p1
I cannot install jetson_multimedia_api with the next command immediately after flashing with the above command.

sudo apt install nvidia-l4t-jetson-multimedia-api

I modified sudo vi /etc/apt/sources.list and made some updates.
Please cross check.

Thank you.

Duplicated with When installing jetson_multimedia_api after flashing