Android GetPhysicalAddress is returning null

When trying to query the PhysicalAddress of a NetworkInterface in C# (in Unity) specifically on Android, it returns empty rather than the mac address. On Windows (In the Unity Editor) it works properly. How can I actually get the physical address?

public static void GetAddresses()
{
    NetworkInterface[] nics = NetworkInterface.GetAllNetworkInterfaces();

    foreach (NetworkInterface adapter in nics)
    {
            Debug.Log($"{adapter.Name} - {adapter.GetPhysicalAddress()}");
    }
}

This returns the following in the log on Android (Samsung, specifically) devices:

wlan0 - 
dummy0 - 
lo - 
rmnet_data1 - 

Ultimately, I'm trying to get a "primary" mac address to tie to a user.