How can I make this program running correctly?

I wanna write a java program that reads two integer numbers from the user, and then displays all the numbers from the first number to the second number that are divisible by 5 or 6, but not both. The output should be displayed as ten numbers per line. This is what I got but it's not working .. can someone help?

public class Testing {
static int num1;
static int num2;
public static void main(String[] args) {

    userInput();
    factorial();

}

public static void userInput() {
    Scanner sc = new Scanner(System.in);

    System.out.println("Enter first number: ");
     num1 = sc.nextInt();

    System.out.println("Enter second number: ");
     num2 = sc.nextInt();
}

public static void factorial() {
    int n;
    int counter = 0;

    for (n = num1; n <= num2; n++) {
        if ((n % 5 == 0 && n % 6 != 0) || (n % 6 == 0 && n % 5 != 0)) {
            System.out.print(n + " ");

            counter = counter++ % 10;
            if (counter == 9) {
                System.out.println();
            }

        }
    }
}
}

If I enter these integers:

Enter first number: 
5
Enter second number: 
90

the program displays that

5 6 10 12 15 18 20 24 25 35 36 40 42 45 48 50 54 55 65 66 70 72 75 78 80 84 85