If there is a lease and you have not violated any of its terms, or the terms of any house rules incorporated by reference into it, then you should not be subject to eviction or any other liability. The best way to respond may be the simplest--ask the landlord or his/her managing agent why they sent you the notice, whether there have been any problems, and whether they believe you have violated any rules or lease provisions (and if so, which ones). It could be that this was sent out as a pro forma notice; it could be that they mistakenly believe you have violated some rule or lease term, and once you are aware of the one involved, you can correct their misapprehension; or it may that you are in fact violating something, even if you're not aware of it--but once you know, you can correct  the problem. Therefore, a request for more information would be a good way to begin.