Ignoring DMs isn't currently possible to my knowledge. However, if it is harrassment, ASims can have a nice chat with the one involved with it.
As a reminder, here is the punishment scale for harrassment, set during the dev meeting:
Admin/Player Harassment - 1st Degree: Warning and Discussion of the expectations of the rules. 2nd Degree: 1-week Ban. 3rd: Perma.
Additionaly, any ban offense and/or degree can be increased with a 10% asset fine if the administration deems it necessary to increase the punitive nature punishment.
Usually, some newbies need to be reminded of the rules. If you are having problems with the one I think, I genuinely hope the player will understand that posting nonsense will not help fulfilling expectations...