O2 Gravity Factory Calibrated SEN0465 isn't giving accurate readings

So I have been trying to read the oxygen values from the SEN0465 sensor for the past two days but am consistently getting innacurate values.

The output I'm getting is:
The device is connected successfully!
Ambient O2 concentration is: 20.90 %vol

Ambient  concentration is: 0.00 %vol

Ambient O2 concentration is: 20.90 %vol

Ambient O2 concentration is: 20.90 %vol

Ambient O2 concentration is: 20.90 %vol

Ambient O2 concentration is: 20.90 %vol

Ambient O2 concentration is: 20.90 %vol

Ambient O2 concentration is: 20.90 %vol

Ambient O2 concentration is: 20.90 %vol

Ambient O2 concentration is: 19.20 %vol

Ambient O2 concentration is: 19.20 %vol

Ambient O2 concentration is: 19.20 %vol

Ambient O2 concentration is: 20.90 %vol

Ambient O2 concentration is: 19.20 %vol

Ambient O2 concentration is: 19.20 %vol

Ambient O2 concentration is: 19.20 %vol

Ambient O2 concentration is: 19.20 %vol

Ambient O2 concentration is: 19.20 %vol

Ambient O2 concentration is: 19.20 %vol

Ambient O2 concentration is: 19.20 %vol

Ambient O2 concentration is: 19.20 %vol

Ambient O2 concentration is: 19.20 %vol

Ambient O2 concentration is: 19.20 %vol

Ambient O2 concentration is: 19.20 %vol

Ambient O2 concentration is: 19.20 %vol

Ambient O2 concentration is: 20.90 %vol

Ambient O2 concentration is: 19.20 %vol

Ambient O2 concentration is: 19.20 %vol

Ambient O2 concentration is: 19.20 %vol

Ambient O2 concentration is: 19.20 %vol

Ambient O2 concentration is: 19.20 %vol

Ambient O2 concentration is: 19.20 %vol

Ambient O2 concentration is: 19.20 %vol

Ambient O2 concentration is: 19.20 %vol

Ambient O2 concentration is: 19.20 %vol


When i keep it under a box it varies by 0.1 percentage (19.1). I don't know what I'm doing wrong. Also the following is my code

/*!

  * @file  readGasConcentration.ino

  * @brief Obtain gas concentration corresponding to the current environment, output as concentration value

  * @n Experimental mode: connect sensor communication pin to the main controller and burn

  * @n Communication mode select, DIP switch SEL: 0: I2C, 1: UART

  * @n Group serial number         Address in the group

  * @n A0 A1 DIP level 00    01    10    11

  * @n 1            0x60  0x61  0x62  0x63

  * @n 2            0x64  0x65  0x66  0x67

  * @n 3            0x68  0x69  0x6A  0x6B

  * @n 4            0x6C  0x6D  0x6E  0x6F

  * @n 5            0x70  0x71  0x72  0x73

  * @n 6 (Default address group) 0x74  0x75  0x76  0x77 (Default address)

  * @n 7            0x78  0x79  0x7A  0x7B

  * @n 8            0x7C  0x7D  0x7E  0x7F

  * @n i2c address select, default to 0x77, A1 and A0 are grouped into 4 I2C addresses.

  * @n             | A0 | A1 |

  * @n             | 0  | 0  |    0x74

  * @n             | 0  | 1  |    0x75

  * @n             | 1  | 0  |    0x76

  * @n             | 1  | 1  |    0x77   default i2c address  

  * @n Experimental phenomenon: view the gas concentration corresponding to the current environment through serial port printing

  * @copyright   Copyright (c) 2010 DFRobot Co.Ltd (http://www.dfrobot.com)

  * @license     The MIT License (MIT)

  * @author      PengKaixing([email protected])

  * @version     V1.0

  * @date        2021-03-28

  * @url         https://github.com/DFRobot/DFRobot_MultiGasSensor

  */

#include "DFRobot_MultiGasSensor.h"

//Turn on by default, using I2C communication at the time, switch to serial port communication after turning off

#define I2C_COMMUNICATION

#ifdef  I2C_COMMUNICATION

#define I2C_ADDRESS    0x74

  DFRobot_GAS_I2C gas(&Wire ,I2C_ADDRESS);

#else

/* ---------------------------------------------------------------------------------------------------------------------

 *    board   |             MCU                | Leonardo/Mega2560/M0 |    UNO    | ESP8266 | ESP32 |  microbit  |   m0  |

 *     VCC    |            3.3V/5V             |        VCC           |    VCC    |   VCC   |  VCC  |     X      |  vcc  |

 *     GND    |              GND               |        GND           |    GND    |   GND   |  GND  |     X      |  gnd  |

 *     RX     |              TX                |     Serial1 TX1      |     5     |   5/D6  |  D2   |     X      |  tx1  |

 *     TX     |              RX                |     Serial1 RX1      |     4     |   4/D7  |  D3   |     X      |  rx1  |

 * ----------------------------------------------------------------------------------------------------------------------*/

/* Baud rate cannot be changed  */

  #if defined(ARDUINO_AVR_UNO) || defined(ESP8266)

    SoftwareSerial mySerial(4, 5);

    DFRobot_GAS_SoftWareUart gas(&mySerial ,9600);

  #elif defined(ESP32)

    DFRobot_GAS_HardWareUart gas(&Serial1 ,9600 ,/*rx*/D2 ,/*tx*/D3);

  #else

    DFRobot_GAS_HardWareUart gas(&Serial1 ,9600);

  #endif

#endif

void setup() {

  //Serial port init for viewing printing output

  Serial.begin(115200);

  //Sensor init, used to init serial port or I2C, depending on the communication mode currently used

  while(!gas.begin())

  {

    Serial.println("NO Deivces !");

    delay(1000);

  }

  Serial.println("The device is connected successfully!");

  //Mode of obtaining data: the main controller needs to request the sensor for data

  gas.changeAcquireMode(gas.PASSIVITY);

  delay(1000);

  /**

   *Turn on temperature compensation: gas.ON : turn on

   *             gas.OFF：turn off

   */

  gas.setTempCompensation(gas.ON);

}

void loop() {

  /**

   *Fill in the parameter readGasConcentration() with the type of gas to be obtained and print

   *The current gas concentration

   *Print with 1s delay each time

   */

  Serial.print("Ambient ");

  Serial.print(gas.queryGasType());

  Serial.print(" concentration is: ");

  Serial.print(gas.readGasConcentrationPPM());

  Serial.println(" %vol");

  Serial.println();

  delay(1000);

}


It is the example code from DFRobot_MultiGasSensor library