Declaring classes in C++ constructor for another class reports "No matching function"

Question

Please be gentle... I don't do much C++ and am trying to tidy up some code.

I'm trying to compile the code below in Arduino Studio, and it keeps throwing an error:

no matching function for call to 'devPort::devPort()'

on the following line:

Sensor(String type, float adjustment, devPort port) {

I've tried moving the devPort part to a new .cpp file and #include'ing it, but I get the same error.

I also tried:

Sensor(String type, float adjustment, devPort::devPort port)

But still the same error.

 class devPort { // There will be 10 'Port's, all pre-defined as unavailable until the boardtype is known
    public:
      devPort(String name, int pin1, int pin2, int mode) {
        this->name = name;
        this->pin1 = pin1;
        this->pin2 = pin2;
        this->mode = mode;
      }
      String name;
      int pin1;
      int pin2;
      int mode;  // -1 = Disabled, 0 = SDA/SCL, 1=DAC, 2=ADC, 3=GPIO
  };
 
  

  // The 'Sensor's will be stored in the flash memory 
  class Sensor {
    public:
      Sensor(String type, float adjustment, devPort port) {   // <--- This is where it complains
        this->type = type;
        this->adjustment = adjustment;
        this->port = port;
      }
      String type;        // Derived from *sensorTypes
      float adjustment;   // +/- adjustment value 
      devPort port;       // Custom Port
  };

I would expect that it should just allow this (and I've tried moving them above/below each other in case of linear compilation).