I sometimes get errors and sometimes I don't?

I'm making a bingo programme. I currently just want to make the 2D array representing the numbers on the bingo card. Column 1 can only contain 1-15 Column 2 16-30 Column 3 31-45 etc....

This is my code so far and sometimes it throws an exception but sometimes it doesn't which is weird.

private int[][] bingoCard = new int [5][5];
public BingoCard()
{
    int [][]bingoCardInit  = new int [5][5];
    bingoCard = bingoCardInit;
}

public void fillInCard()
{
    int arrayIndex = 0;
    Integer[] arr = new Integer[16];
    for (int i = 1; i <= 15; i++) 
    {
        arr[i] = i;
    }
    Collections.shuffle(Arrays.asList(arr));
    for(int rowIndex = 0; rowIndex<5; rowIndex++)
    {
        bingoCard[0][rowIndex] = arr[rowIndex];
        System.out.println(bingoCard[0][rowIndex]);
    }

    Integer[] arr1 = new Integer[16];
    for (int i = 16; i <= 30; i++) 
    {
        arr1 [arrayIndex]= i;
        arrayIndex++;
    }
    Collections.shuffle(Arrays.asList(arr1));
    arrayIndex = 0;
    for(int rowIndex = 0; rowIndex<5; rowIndex++)
    {
        bingoCard[1][arrayIndex] = arr1[rowIndex];
        System.out.println(bingoCard[1][arrayIndex]);
        arrayIndex++;
    }

    arrayIndex = 0;
    Integer[] arr2 = new Integer[16];
    for (int i = 31; i <= 45; i++) 
    {
        arr2 [arrayIndex]= i;
        arrayIndex++;
    }
    Collections.shuffle(Arrays.asList(arr2));
    arrayIndex = 0;
    for(int rowIndex = 0; rowIndex<5; rowIndex++)
    {
        bingoCard[2][arrayIndex] = arr2[rowIndex];
        System.out.println(bingoCard[2][arrayIndex]);
        arrayIndex++;
    }

    arrayIndex = 0;
    Integer[] arr3 = new Integer[16];
    for (int i = 46; i <= 60; i++) 
    {
        arr3 [arrayIndex]= i;
        arrayIndex++;
    }
    Collections.shuffle(Arrays.asList(arr3));
    arrayIndex = 0;
    for(int rowIndex = 0; rowIndex<5; rowIndex++)
    {
        bingoCard[3][arrayIndex] = arr3[rowIndex];
        System.out.println(bingoCard[3][arrayIndex]);
        arrayIndex++;
    }

}

I'm just wondering why it sometimes throws an exception. Thank you