Dog barking/crying all night

So I live at this apartment complex with my bf and almost 2 year old, the walls are paper thin and you can hear almost everything, the thing is that my neighbors upstarts have a dog and at least one time every week they left him all day and all night, so he cries, barks and scratches all night and part of the morning which is really annoying, my two year old wakes up constantly cause of it... I’ve been thinking about putting a note on their door since I never get to see them to talk to them but idk what to put without sounding rude cause I don’t want trouble, or should I call the office and have them talk to them? I need advice !