If you are having problems with your neighbor and you would like to tell them about it, here is a template you can use to write a complaint letter to your neighbor.
Good Day! Hope this letter finds you well. I have heard that you are causing disturbances to our property. As much as I would not like to ruin our relationship as neighbors, I want something to be done immediately.
This is not something that we should just let go. This is clearly a situation that needs to be addressed right away. Right, now, you are not being a good neighbor so I hope this is just a mistake on your part. Hope you can do what is right and do something about it.
Just like how I am a good neighbor to you, let us hope that you will do the same. I would not want us to have a bad relationship because we are stuck with each other for the foreseeable future.