Help me in solving FLOW001 problem

My issue

Exception in thread “main” java.util.NoSuchElementException
at java.base/java.util.Scanner.throwFor(Scanner.java:937)
at java.base/java.util.Scanner.next(Scanner.java:1594)
at java.base/java.util.Scanner.nextInt(Scanner.java:2258)
at java.base/java.util.Scanner.nextInt(Scanner.java:2212)
at Codechef.main(Main.java:18) what is this??

My code

/* package codechef; // don't place package name! */

import java.util.*;
import java.lang.*;
import java.io.*;

/* Name of the class has to be "Main" only if the class is public. */
class Codechef
{
	public static void main (String[] args) throws java.lang.Exception
	{
		// your code goes here
			Scanner scn = new Scanner(System.in);
		int t = scn.nextInt();
		
		while(t > 0){
		    
		    int a = scn.nextInt();
		    int b = scn.nextInt();
		    int c = a + b;
		    System.out.println(c);
	}
	
	}
}

Learning course: Practice Java
Problem Link: CodeChef: Practical coding for everyone

@himanshu_7492
you have forgotten to decrement the while there should be a t–;