I am having the same issue as Orin flashed with JetPack 5.0 using SDKManger show “Test Key is Used” Error - Jetson & Embedded Systems / Jetson AGX Orin - NVIDIA Developer Forums.
I flashed the first time using SDK manager. I flashed the second time using flash.sh. Both flashes were from a Linux host machine. Any ideas on how to fix this problem? It did say successfully flashed and “Reset the board to boot from internal eMMC.” when I finished.