Residents reported someone knocking at the door. What should the landlord say?

Contact the property first. If you often knock on the door, the victim can report the case to the public security organ for education. If the public security organ's education is ineffective and the other party still refuses to change the harassment behavior, causing mental distress to the victim, then the victim can bring a lawsuit to the court and ask the other party to stop the infringement, bear civil liability and pay compensation for mental damage.

When a stranger knocks at the door, you must not open the door. If you hear someone calling, you must first see who it is through the cat's eye. If you are a stranger, never open the door. You should refuse him politely.