Generate random numbers after 5 seconda

I am making sport app where random numbers generate on display. And here is my problem. How to generate this numbers always after. I've had this problem resolved from tutorial but I don't know how this area of ​​code has disappeared yesterday. If you know how to undo applications from two days ago you don't need to solve my problem.

Random r;
String[] kombinacje = {"1-2", "1-1-2", "1-2-3-2", "1-2-5-2", "1-6-3-2", "2-3-2"};
@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main6);
    tv1 = (TextView) findViewById(R.id.textView23);
    tv2 = (TextView) findViewById(R.id.textView24);
    tv3 = (TextView) findViewById(R.id.textView25);

    tv3.setText(kombinacje[new Random().nextInt(kombinacje.length)]);

    r = new Random();
    String runda = getIntent().getStringExtra("RUNDA");
    final long millisInput = getTimeInLong(runda) * 1000;
    CountDownTimer countDownTimer = new CountDownTimer(4000, 1000) {
        @Override
        public void onTick(long millisUntilFinished) {
            tv2.setText("Przygotuj się:\n " + (millisUntilFinished / 1000));
        }
        @Override
        public void onFinish() {
            final java.util.Random rand = java.util.concurrent.ThreadLocalRandom.current();
            mCountDownTimer = new CountDownTimer(millisInput, 1000) {
                @Override
                public void onTick(long millisUntilFinished) {
                    mTimeLeftInMillis = millisUntilFinished;
                    updateCountDownText()
                }

                @Override
                public void onFinish() {
                    tv1.setText("Koniec Rundy");
                    MediaPlayer ring = MediaPlayer.create(Main6Activity.this, R.raw.ring1);

                    ring.start();
                    tv3.setText("Przerwa");
                }
            }.start();
            updateCountDownText();
            tv2.setText("Walka!");

                MediaPlayer ring = MediaPlayer.create(Main6Activity.this, R.raw.ring1);

                ring.start();


    }.start();
}

private void updateCountDownText(){
    int hours = (int) (mTimeLeftInMillis / 1000) / 3600;
    int minutes = (int) ((mTimeLeftInMillis / 1000) % 3600) / 60;
    int seconds = (int) (mTimeLeftInMillis / 1000) % 60;
    String timeLeftFormatted;

    timeLeftFormatted = String.format(Locale.getDefault(),
            "%02d:%02d", minutes, seconds);

    tv1.setText(timeLeftFormatted);
}

public long getTimeInLong(String input) {
    StringBuilder builder = new StringBuilder();
    String[] splittedString = input.split(":");
    builder.append(splittedString[0]);
    builder.append(splittedString[1]);

    return Long.parseLong(builder.toString());
}

private void setTime(long milliseconds) {
    resetTimer();

    mStartTimeInMillis = milliseconds;
}

private void resetTimer() {
    mTimeLeftInMillis = mStartTimeInMillis;
    updateCountDownText();
}

}