Dogs bark at every opportunity. Thats just the way it is. This barking can be excessive in some cases and may indicate a problem. Dogs might bark excessively for a variety of reasons including boredom loneliness and distress. When your neighbors dog barks all night it disturbs the peace and becomes a nuisance.
The environmental health authorities in your area can be contacted regarding this issue. A formal request could be made to the pups owner to stop the dog from barking so loudly. If the owner is unsuccessful the puppy could be taken from them.