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This is NOT my code; was posted on Project Hub. I tried to use the code (humidity controller) but it returns an error on line 270:

else if (DHT.humidity >= setpoint + 3 and syson == true) { //if humidity is 3% above setpoint

Error: expected primary-expression before '.' token

The OP is not responding to comments and I'm no expert. Would appreciate if someone could help debug the code; Thanks!

//HUMIDITY CONTROLLER 1.1
//written for NANO
//controls and displays relative humidity
//sesnor used is DHT11
//uses active-low relay module to control live lines for 2 standard electrical outlets
//uses i2c lcd to display humidity and humidity setting
//turns display off during inactivity
//setting is adjustable from 10%-90% using 2 buttons
//backlight of LCD is controlled by pin 4, connected to top LED jumper pin on i2c backpack
//serial communications to monitor to ensure all code is working.
//added: "system off" function - allows both outlets to be turned off
// █ G █ L █ O █ B █ A █ L █ S █
#include <Wire.h>
#include <LiquidCrystal_I2C.h>
#include <dht.h>
// set the LCD address to 0x27 for a 16 chars and 2 line display
LiquidCrystal_I2C lcd(0x27, 16, 2); 
dht DHT;
#define DHT11_PIN A2
//buttons and variables to adjust calibration
int calupbtn = A0;
int calup;
int caldownbtn = A1;
int caldown;
//i2c PINS A4, A5
//pin for turning on humidifier relay
int humidifier = 3;
//pin for turning on the fan relay
int fan = 2;
//pin for turning on LCD backlights
int lcdlight = 4;
//calibration variable
int setpoint = 50; //feedback setpoint. 
bool calstate = false; //enables calibration adjustments only when LCD is ON.
//backlight timing variables
int displtime = 12000; //amount of time the display is to be on before turning off
unsigned long displtimeon; //last recorded time display timer was reset
int calunlock = 0; //loop counter for unlocking calibration 
//sensor timing variables
unsigned long lastcheck; //last time DHT was read
long interval = 30000; //time between DHT readings
//system variables
bool syson = true; //reference for system on/off. 
byte systog = 2; //even number toggles on, odds toggle off
int syslock = 0; //loop counter for unlocking system toggle
// █ S █ E █ T █ U █ P █ + █ + █ + █ + █ + █ + █ + █ + █ + █ + █ + █ + █ + █ + █
void setup(){
 Serial.begin(9600); //serial communication used to ensure code is working correctly.
 
 lcd.init(); //initialize LCD
 lcd.backlight(); //enable LCD backlight, but doesn't turn it on
 lastcheck = 0;
 digitalWrite(lcdlight, HIGH);
 Serial.println("STARTING");
 lcd.print(" STARTING");
 //pin assignments
 pinMode(calupbtn, INPUT);
 pinMode(caldownbtn, INPUT);
 pinMode(humidifier, OUTPUT);
 pinMode(fan, OUTPUT);
 pinMode(lcdlight, OUTPUT);
 delay(1000);
 
 //test fan
 lcd.setCursor(0,1);
 lcd.print("<FAN> HMDFR "); 
 digitalWrite(fan, LOW);
 digitalWrite(humidifier, HIGH);
 delay(6000);
 //test humidifier
 lcd.setCursor(0,1);
 lcd.print(" FAN <HMDFR> ");
 digitalWrite(fan, HIGH);
 digitalWrite(humidifier, LOW);
 delay(6000);
 //stop startup test
 digitalWrite(humidifier, HIGH);
 digitalWrite(fan, HIGH);
 lcd.clear();
 displtimeon = millis();
 int chk = DHT.read11(DHT11_PIN);
 lastcheck = millis();
 lcd.setCursor(0,0);
 lcd.print("Humidity: ");
 lcd.setCursor(13,0);
 lcd.print(DHT.humidity);
 lcd.setCursor(15,0);
 lcd.print("% ");
 lcd.setCursor(0,1);
 lcd.print("setting: ");
 lcd.setCursor(13,1);
 lcd.print(setpoint);
 lcd.setCursor(15,1);
 lcd.print("% ");
 delay(100);
}
// █ L █ O █ O █ P █ = █ = █ = █ = █ = █ = █ = █ = █ = █ = █ = █ = █ = █ = █ = █
void loop(){
 //check calibration buttons
 calup = digitalRead(calupbtn);
 caldown = digitalRead(caldownbtn);
 if(calup == HIGH and caldown == HIGH){ //--------SYSTEM TOGGLE
 syslock ++;
 Serial.println(syslock);
 if(syslock == 20){ //if both buttons held down for this many loops
 systog++;
 if(systog % 2 == 1){ //--------SYSTEM OFF
 syson = false;
 digitalWrite(fan, HIGH);
 digitalWrite(humidifier, HIGH);
 digitalWrite(lcdlight, HIGH);
 Serial.println("SYSTEM TURNED OFF");
 lcd.clear();
 lcd.print(" SYSTEM OFF");
 lcd.setCursor(0,1);
 lcd.print(" hold both btns");
 delay(2000);
 lcd.setCursor(0,1);
 lcd.print(" to turn on ");
 displtimeon = millis();
 }
 if(systog % 2 == 0){ //--------SYSTEM ON
 syson = true;
 Serial.println("SYSTEM TURNED ON");
 digitalWrite(lcdlight, HIGH);
 lcd.clear();
 lcd.print(" SYSTEM ON");
 delay(2000);
 lcd.clear();
 displtimeon = millis();
 }
 syslock = 0;
 }
 }
 else(syslock = 0);
 
 //read humidity at appropriate intervals
 if(millis() > lastcheck + interval and syson == true){ //read the DHT humidity
 int chk = DHT.read11(DHT11_PIN);
 lastcheck = millis();
 Serial.print("DHT read = ");
 Serial.print(DHT.humidity);
 Serial.print("%");
 Serial.println(" ");
 }
 //turn on the led lights when calibration buttons are pressed
 if(calup == HIGH xor caldown == HIGH){
 digitalWrite(lcdlight, HIGH);
 calstate = true;
 displtimeon = millis(); //set display timer
 Serial.println("cal btn ACTIVE");
 if(syson == false){
 digitalWrite(lcdlight, HIGH);
 lcd.clear();
 lcd.print(" SYSTEM OFF");
 lcd.setCursor(0,1);
 lcd.print(" hold both btns");
 delay(3000);
 lcd.setCursor(0,1);
 lcd.print(" to turn on ");
 displtimeon = millis();
 }
 }
 if(calstate == true and syson == true){ //--------DISPLAY ROUTINE
 Serial.println("printing display");
 //display variables on LCD
 lcd.setCursor(0,0);
 lcd.print("Humidity: ");
 lcd.setCursor(13,0);
 lcd.print(DHT.humidity);
 lcd.setCursor(15,0);
 lcd.print("% ");
 lcd.setCursor(0,1);
 lcd.print("setting: ");
 lcd.setCursor(13,1);
 lcd.print(setpoint);
 lcd.setCursor(15,1);
 lcd.print("% ");
 delay(100);
 calunlock ++; 
 //keeps calibration locked until display cycles 5 times after initially turned on
 //prevents adjustments on initial button press.
 }
//--------CALIBRATION ADJUSTMENTS
 if(calup == HIGH and caldown == LOW and calstate == true and syson == true){ 
 if(setpoint < 90 and calunlock > 5){ 
 setpoint = setpoint + 5; //increase setpoint 
 Serial.println("adj setpoint up");
 }
 Serial.println(setpoint);
 delay(100);
 displtimeon = millis(); //reset backlight timeout
 }
 if(caldown == HIGH and calup == LOW and calstate == true and syson == true){
 if(setpoint > 10 and calunlock > 5){
 setpoint = setpoint - 5; //decrease setpoint
 Serial.println("adj setpoint dn");
 }
 Serial.println(setpoint);
 delay(100); 
 displtimeon = millis(); //reset backlight timeout
 }
 if(millis() > displtimeon + displtime){ //-----------------BACKLIGHT TIMEOUT
 digitalWrite(lcdlight, LOW); //turn off the screen
 calstate = false;
 Serial.println("displ + backlights off");
 lcd.clear();
 calunlock = 0; //lock calibration
 }
 if(millis() < lastcheck){
 lastcheck = millis(); //reset timers in a millisecond rollover
 }
 //--------SETPOINT ERROR PROCEDURE
 if(setpoint > 91 or setpoint < 9){ //in case setpoint is ever out of bounds
 Serial.println("O/B ERROR");
 digitalWrite(lcdlight, HIGH);
 lcd.clear();
 lcd.print("O/B ERROR"); //display error message on lcd
 lcd.setCursor(0,1);
 lcd.print("RESETTING");
 delay(1000);
 for(int count = 9; count >= 0; count = count - 1){
 lcd.setCursor(15,1);
 lcd.print(count); //count down from 10
 delay(1000);
 }
 setpoint = 50; //reset setpoint at 50.
 displtimeon = millis();
 }
 //turn on humidifier relay if below setpoint --------RELAY CONTROL
 //RELAY MODULE IS ACTIVE LOW
 if(DHT.humidity <= setpoint - 3 and syson == true){ //if humidity is 3% lower than setpoint
 Serial.println("humidifier ON, fan OFF"); 
 digitalWrite(humidifier, LOW); //turn on humidifier
 digitalWrite(fan, HIGH);
 }
 else if(DHT.humidity >= setpoint + 3 and syson == true){ //if humidity is 3% above setpoint
 Serial.println("humidifier OFF, fan ON");
 digitalWrite(humidifier, HIGH); //turn on fan
 digitalWrite(fan, LOW);
 }
 else{
 Serial.println("all off"); //if humidity is within 3% of setpoint
 digitalWrite(humidifier, HIGH); //turn both off
 digitalWrite(fan, HIGH);
 }
 //delay(700); //un-comment for serial debugging
 Serial.print("setpoint = ");
 Serial.println(setpoint);
 //delay(700); //un-comment for serial debugging
}