Moving STDIO serial pin

Hi all,

i try to move STDIO serial RX pin on my nRF52_DK.
I’ve modified mbed_app.json like this:

    "target_overrides": {
        "*": {
            "platform.stdio-convert-newlines": true,
            "platform.stdio-baud-rate": 115200,
            "platform.default-serial-baud-rate": 115200,
            "target.stdio_uart_rx": "P0_18",
            "target.stdio_uart_tx": "P0_6",
...

When I compile the define MBED_CONF_TARGET_STDIO_UART_RX does not included into mbed_config.h

I use mbed-os 6.14. Can you help me what i missed?

Thank you, best regards,
David