core java. isInteger methods. Finding bug.

public static int isInputInteger(){
		@SuppressWarnings("resource")
		Scanner input = new Scanner(System.in);   

		int correctNumber;
		
			while(true){   
			input.nextLine();
				    if(input.hasNextInt()){   
				    	correctNumber = input.nextInt();
				        break;
				    }
				    else{
				    	System.out.println("Your input isn't integer.Please, try again. ");
				    }
			}
			return correctNumber;
			}

class PrintFromInput {

	protected static int  printNumber() {
    	System.out.printf("Please, enter integer: ");
    	int intYourConsoleInput = Assert.isInputInteger();
         return intYourConsoleInput; 
    }
}

public class Task {
    public static void main(String[] args) {
    	
    	System.out.println("Congratulation! Your correct integer input is: "+ PrintFromInput.printNumber()); 
    	
    }
}

Inside class Assert there is a method "isInputInteger" everything work but not as I expect :
Session 1
input : f
output: {nothing }
input : f
output : Your input isn't integer.Please, try again.
input: g
output : Your input isn't integer.Please, try again.
input : 3
Congratulation! Your correct integer input is: 3
Session OVER
My question is why there isn't any message after first "f". Please, help me to find bug. Thx in advance !