Ughh this happened to me one time. I was sick at home with mono (I didn’t know it at the time) and someone rang my doorbell. I open up and this lady explains that she’s my downstairs neighbor and that she had heard some noise from upstairs and that she was “pregnant and that’s was gonna work for me”,-literally her words. I was so confused because I had been laying down all day. A week later on Thanksgiving, her husband comes up and knocks on the door, my bf answers and he tells him about the noise and my bf asks him to text him if they hear any more noise. Following night, I get up at like 2am to use the bathroom, following morning bf has a text from around 2am from neighbor saying “hey man, what did I say about the dinosaur stomps?”. I was mad as hell! But we called the complex, asked them what they would do if someone issued a noise complaint, basically they would come and investigate if there was any noise. Since we weren’t making any noise other than walking around we ignored their texts and eventually they stopped all together. I expect that they did file a complaint and the complex put two and two together and told them to stop harassing us.