Yours address,
Place of where you stay,
Your neighbor address
(You don't need to write the place where he stays cause its the same place)
(State- same as you done with the place)

Dear "His fathers name"
As you know I have seen you from my childhood, but I am here to complain you for some things that you need to take care.

Well,the thing is that your son plays very loud music at night and I have to study upto midnight so therefore can you please tell your son to not to play loud music and it is not disturbing me but also the other people. And, if any step is not taken then I will have no decision but to call authorities so please kindly take this matter as a serious issue.

Here I am ending and I hope you will take this matter seriously and will took the responsible for this. Here I am ending well wishes to you and your family.

Yours sincerely, 
Your name

*If you have any troubles feel free to ask me*
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