Odroid n2+ and GPIO serial port

For my home assistant project I need working onboard pin8 and pin10 (RX, TX) working for serial communication. My problem is, that normaly this pins are mapped as /dev/ttyAML1 (hope so, it’s odroid n2+), but it’s not working. How can I enable this UART pins ? Or how to check what is correct adress of this pins to get serial communication working ?
Thaks for help

What operating system?

It’s DietPi
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