Turbidity Sensor Problem.

I have followed all of the steps to make the turbidity sensor. The parts are all tucked, and they are not flipped. But, my voltage has been stuck at 1.50 and below and doesn't move. What do I do? The ntu stays at 3,000 because there isn't sufficient voltage from the arduino to the sensor for the turbidity sensor to create a data value. I have legit tried everything. Here is my code:

#include <Wire.h>

#include <LiquidCrystal_I2C.h> // Corrected library name

// Initialize the LCD with the I2C address (0x27) and screen dimensions (16 columns, 2 rows)

LiquidCrystal_I2C lcd(0x27, 16, 2);

const int sensorPin = A1; // Reads physical pin A0 due to board label swap

void setup() {

Serial.begin(9600);

lcd.init(); // Correct method to initialize the I2C LCD screen

lcd.backlight(); // Turns on the LCD backlight so you can see the text

lcd.setCursor(0, 0);

lcd.print("Turbidity Test");

delay(1500);

lcd.clear();

}

void loop() {

// 1. Take ONE reading and calculate voltage immediately

int rawValue = analogRead(sensorPin);

float voltage = rawValue * (5.0 / 1024.0);

// 2. Calculate NTU

float ntu = 0.0;

if (voltage >= 2.5) {

ntu = -1120.4 * (voltage * voltage) + 5742.3 * voltage - 4353.8;

if (ntu < 0) ntu = 0;

} else {

ntu = 3000.0;

}

// 3. Print the EXACT SAME values to Serial Monitor

Serial.print("Raw: ");

Serial.print(rawValue);

Serial.print(" | Volt: ");

Serial.print(voltage, 2);

Serial.print("V | NTU: ");

Serial.println(ntu, 1);

// 4. Print the EXACT SAME values to LCD Screen

lcd.setCursor(0, 0);

lcd.print("Volt: ");

lcd.print(voltage, 2);

lcd.print("V "); // Spaces clear trailing characters

lcd.setCursor(0, 1);

lcd.print("NTU: ");

lcd.print(ntu, 1);

lcd.print(" "); // Spaces clear trailing characters

delay(1000);

}

The sensors are all brand new, and I had bought two of the same sensor, which has all shown the same thing.