pin 9 configuration.

I have an application that tries to configure pin 9 of port 0 on the nrf52840. this pin is reserved for NFC use.
in one application it was enough to add:

&uicr {
    nfct-pins-as-gpios;
};

to the device tree.

I tried to implement the same logic on another app, a testing app, but got this error:
 

I manged to fix this by getting pin 09 out of the reserved range in the overlay file: 

&gpio0 {
    gpio-reserved-ranges = <0 2>, <6 1>, <8 1>, <17 7>;
};

but I cant understand how could it be that in one application that's needed and on the other it is not.

thanks in advance

-Shlomo
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