As of this writing, residents can engage in abusive behavior by sending L$ to people who have blocked them. This enables the unwanted receipt of messages from blocked parties using the L$ Pay notes as an attack vector.
When someone is blocked, all methods of communication or interaction should be prohibited at the forefront. People circumventing this are not only harassing people, but exploiting a safety exploit in the payment system to continue harassing people, which given the negligble cost of L$ on an individual level, these attacks could be persistent.