Help me in solving ERR5 problem

help
,
1

My issue

can you explain this problem in details

My code

// Submit to check the output
import java.util.*;

class Rectangle {
    public static int calculateArea(int length, int width) throws NegativeValueException {
        if (length < 0 || width < 0) {
            throw new NegativeValueException("Error: length or width cannot be negative");
        }
        return length * width;
    }
}

class NegativeValueException extends Exception {
    public NegativeValueException(String message) {
        super(message);
    }
}

class Codechef
{
	public static void main (String[] args)
	{
		try {
            int length = -5;
            int width = 3;

            Rectangle rectangle = new Rectangle();
            int area = rectangle.calculateArea(length, width);
            System.out.println("Area: " + area);
        }
        catch (NegativeValueException e) {
            System.out.println(e.getMessage());
        }
	}
}

Learning course: Learn Advance Java
Problem Link: CodeChef: Practical coding for everyone