Neighbours having loud sex

S • TTC #1

So we have been in our home for 2 years now we own our home. Our new neighbours are renting the property next door they’ve been there for over 6 months now and for the six months they have been having extremely loud sex at stupid o’clock at night. We have been asleep and it’s literally woken us up. what would you do ? I have written them a letter but any advice would be appreciated.

Update:

I have re written the letter. What do you think