NPK output sensor displaying random characters please help me

here is my code

#include <SoftwareSerial.h>
#include <Wire.h>

#define RE 8
#define DE 7
 
// The following are the Inquiry frames which are send to the NPK sensor
//for reading the Nitrogen, Phosphorus, and Potassium values
// We defined three arrays with names nitro_inquiry_frame, phos_inquiry_frame, and pota_inquiry_frame 
// Each inquiry frame have 8 values
const byte nitro_inquiry_frame[] = {0x01,0x03, 0x00, 0x1e, 0x00, 0x01, 0xe4, 0x0c};
const byte phos_inquiry_frame[] = {0x01,0x03, 0x00, 0x1f, 0x00, 0x01, 0xb5, 0xcc};
const byte pota_inquiry_frame[] = {0x01,0x03, 0x00, 0x20, 0x00, 0x01, 0x85, 0xc0};
 
byte values[11];
SoftwareSerial modbus(2,3);
 
void setup() {
  Serial.begin(9600);
  modbus.begin(9600);
  pinMode(RE, OUTPUT);
  pinMode(DE, OUTPUT);
  
  delay(1000);
}
 
void loop() {
  // we will need three variables of the type byte to store the values of 
  // Nitrogen, phosphorus, and Potassium. 
  byte nitrogen_val,phosphorus_val,potassium_val;
 
  nitrogen_val = nitrogen();
  delay(2500);
  phosphorus_val = phosphorous();
  delay(2500);
  potassium_val = potassium();
  delay(2500);
  
  
  Serial.print("Nitrogen_Val: ");
  Serial.print(nitrogen_val);
  Serial.println(" mg/kg");
  Serial.print("Phosphorous_Val: ");
  Serial.print(phosphorus_val);
  Serial.println(" mg/kg");
  Serial.print("Potassium_Val: ");
  Serial.print(potassium_val);
  Serial.println(" mg/kg");
  delay(1000);
 

}
 
/*
 * Now, we will need to create three user-defined functions to read the Nitrogen, Phosphorus, and Potassium values
 * These user-defined functions are going to be of the type byte
 */
 
byte nitrogen(){
  digitalWrite(DE,HIGH);
  digitalWrite(RE,HIGH);
  delay(10);
  if(modbus.write(nitro_inquiry_frame,sizeof(nitro_inquiry_frame))==8){
    digitalWrite(DE,LOW);
    digitalWrite(RE,LOW);
    // When we send the inquiry frame to the NPK sensor, then it replies with the response frame
    // now we will read the response frame, and store the values in the values[] arrary, we will be using a for loop.
    for(byte i=0;i<7;i++){
    //Serial.print(modbus.read(),HEX);
    values[i] = modbus.read();
   // Serial.print(values[i],HEX);
    }
    Serial.println();
  }
  return values[4]; // returns the Nigtrogen value only, which is stored at location 4 in the array
}
 
byte phosphorous(){
  digitalWrite(DE,HIGH);
  digitalWrite(RE,HIGH);
  delay(10);
  if(modbus.write(phos_inquiry_frame,sizeof(phos_inquiry_frame))==8){
    digitalWrite(DE,LOW);
    digitalWrite(RE,LOW);
    for(byte i=0;i<7;i++){
    //Serial.print(modbus.read(),HEX);
    values[i] = modbus.read();
   // Serial.print(values[i],HEX);
    }
    Serial.println();
  }
  return values[4];
}
 
byte potassium(){
  digitalWrite(DE,HIGH);
  digitalWrite(RE,HIGH);
  delay(10);
  if(modbus.write(pota_inquiry_frame,sizeof(pota_inquiry_frame))==8){
    digitalWrite(DE,LOW);
    digitalWrite(RE,LOW);
    for(byte i=0;i<7;i++){
    //Serial.print(modbus.read(),HEX);
    values[i] = modbus.read();
    //Serial.print(values[i],HEX);
    }
    Serial.println();
  }
  return values[4];
}

Can you get a simple "hello world" in setup() to display correctly?

i can't even after trying this

with or without while(Serial) both are not displaying anything