General Customer support phone number is: (973) 275-5555
And the ticket support number is (973) 491-8810
They are pretty much quite understanding when it comes to accidentally activating more than 1 ticket, changing devices, etc.
We sometimes think in big cities these federal/popular agencies do their business services bureaucratically to meet the high demands in the cities, but not so for NJ Transit, at least not for the most parts.