What I've put above is an interpretation, in the negative, of the actual statute.
The actual statute says:
C. Notwithstanding subsection A of this section, the court shall not initiate collection procedures on an unpaid civil penalty, notify the department to suspend a person's driver license, permit or privilege to drive a motor vehicle in this state or notify the department to refuse to renew a vehicle registration for an unpaid civil traffic violation if all of the following apply:
1. The unpaid civil penalty is for a traffic violation for which the final disposition occurs more than thirty-six months before the court initiates collection proceedings. (This is true for you).
2. The court does not have a paper or electronic record dated within thirty-six months after the traffic violation occurs indicating that the responsible person was notified that the civil penalty is unpaid and due. (This may be true for you, but just because you don't have the notice doesn't mean they don't have something saying they sent you notice.)
3. The court has not notified the department to suspend the responsible person's driver license or permit or privilege to drive a motor vehicle in this state. (Did they do this?)
4. The court has not notified either the responsible person or the department about the court's request to the department to refuse to renew the responsible person's vehicle registration pursuant to article 5 of this chapter. (Did they do this?)
5. The court does not have a record of extending the time for payment of the civil penalty or providing for installment payments. (Did they do this?)
Which means if ALL of the things above are true, they can not (sucessfully) initiate collection proceedings and you can raise this statute as a defense. If they can show ANY of the 5 things above, then they have preserved their right to collect.
It's nothing to do with notifying you in the last 3 years....but rather, within three years of the actual offense.