Gerar 12 números 6 em cada TextView na TextView 3 mostra repetidos na TextView 1 e 2

Set<Integer> uniqueNumbers1 = new HashSet<>();
while (uniqueNumbers1.size() < 6) {
    uniqueNumbers1.add((int)(Math.random()*10));
}
List<Integer> randomNumbers1 = new ArrayList<>(uniqueNumbers1);

TextView textView1 = (TextView) findViewById(R.id.textview1);
textView1.setText(TextUtils.join(", ", randomNumbers1));

Set<Integer> uniqueNumbers2 = new HashSet<>();
while (uniqueNumbers2.size() < 6) {
    uniqueNumbers2.add((int)(Math.random()*10));
}
List<Integer> randomNumbers2 = new ArrayList<>(uniqueNumbers2);

TextView textView2 = (TextView) findViewById(R.id.textview2);
textView2.setText(TextUtils.join(", ", randomNumbers2));

List<Integer> randomNumbers3 = new ArrayList<>(randomNumbers1);
randomNumbers3.retainAll(randomNumbers2);

TextView textView3 = (TextView) findViewById(R.id.textview3);
textView3.setText(TextUtils.join(", ", randomNumbers3));