Can't get APC220 to work

#include <SoftwareSerial.h>
 
//rafaboi
 
const int rxPin = 0;
const int txPin = 1;
const int setPin = 2;
const int enPin = 3;
const int fiveV = 4;
 
 
SoftwareSerial thing(rxPin, txPin);
 
void setup() {
  // put your setup code here, to run once:
  Serial.begin(9600);
  thing.begin(9600);
  pinMode(setPin, OUTPUT);
  digitalWrite(setPin, HIGH);
  pinMode(fiveV, OUTPUT);
  digitalWrite(fiveV, HIGH);
  pinMode(enPin, OUTPUT);
  digitalWrite(enPin, HIGH);
  pinMode(LED_BUILTIN, OUTPUT);
  digitalWrite(LED_BUILTIN, HIGH);
  delay(1000);
  digitalWrite(LED_BUILTIN, LOW);
  digitalWrite(setPin, LOW);
  thing.listen();
  thing.println("RD");
  delay(10);
  Serial.println("");
  Serial.println("here we gooo:");
  /*while (thing.available()) {
    Serial.print(thing.read());
  }*/
  Serial.println("done!");
  digitalWrite(setPin, HIGH);
 
}
 
void loop() {
  // put your main code here, to run repeatedly:
  if (thing.available() > 0) {
    Serial.print(thing.read());
  }
 
}