What you have probably been told

That if you had been truly repentant, you would have stopped. That going back proves the last tawbah was not real. That there is a number of times after which it stops being accepted.

None of that is in the sound material, and one of those claims is directly contradicted by a report in Bukhari. But before any of the correcting, there is a verse to put down first, because the order matters and the Qur'an itself puts it in this order.