ESP32 to XIAO nrf52840

[diegocastillo1801]

Hi, i made a project with an ESP32 WROOM 32D, the esp32 read the value of a sensor connected on one pin and then sends the data via bluetooth to an app created on app inventor with the bluetooth serial, but now i want to use the xiao nrf52840 because is smaller, but the problem is that i can´t make the xiao display on the bluetooth devices list of the android smartphone and i need it to connect it to the app, any ideas or examples of how can i do that? i tried a lot of codes and libraries but i failed, this is my code:

#include <BluetoothSerial.h>

BluetoothSerial SerialBT;

const int ledpin=2;

void setup() {
  Serial.begin(115200);
   pinMode(ledpin, OUTPUT);    
  SerialBT.begin("ESP32"); // Nombre del dispositivo Bluetooth
  pinMode(34, INPUT); // Sensor conectado al pin 34
}

  void loop() {
  bool sensorValue = analogRead(34) < 2500;
  SerialBT.println(sensorValue);
  Serial.print(analogRead(34));
  Serial.println("");
  
   if (analogRead(34) < 2000.) {
    digitalWrite(ledpin, HIGH);  // Enciende el LED
  } else {
    digitalWrite(ledpin, LOW);   // Apaga el LED
  }
  
    
  delay(1000);
}

`