Ovulation occurs between periods. So, if you had a period last month and your period is overdue this month, you should have ovulated between that last period and now.
If you have never had a period in your life, you will not be ovulating. If you have irregular cycles, your ovulation time is fairly unpredictable.
...so ovulation is possible even without a period...hmm
If your period is overdue, it's late according to what the tracker has seen to be your norm. Ovulation should have already occurred for this particular cycle.