A203 V2 XAVIER NX UART1 not working (203_jp5.0.2.zip)

I have installed the Jetpack 5.0.2 with ubuntu 20.0.4 on a XAVIER NX A203 V2 carrier board, successfully. And I was able to use the GPIOs.

Now I need to use the UART1 and it is not working. I’m using a loop-back connection and Cutecom for testing. Here the available ports: ttyTHS0, ttyTHS1 and ttyTHS4. I tested all without success ( no RX return)

Do I missing something? Is there any procedure to make it works?