after 2 month pause I wanted to work again with my jetson nano (B01). I tried for the first time to flash an sd card with ubuntu 20.04. First the system booted up and I could work with it. After 2 sessions it won’t boot again. So I tried flashing the sd card again but it wasn’t working anymore. So I considered the card as broken and bought a new one but it also failed. I need help to check whats wrong with my jetson.