My name is Hugo and I am a retired behavior specialist. I can help
but I should have more information . Is your dog confined to a yard or put on a tether in the yard or in front of the house .
It has taken him a long time to learn this bad habit and it will take time and patience to break him of it. Try something that
works for me , it may seam cruel but it is a valid way of making
a point that your dog will understand . When he barks wrap
some masking tape around his mussel and leave it there for
Two or three hours, make sure that you do not interfear with
his breathing . You may have to do this several times it will not
cure the problem overnight. Eventually all you will have to do
when he barks is show him the tape. If this dose not work his
problem may be deeper rooted and I will require more history
but I am sure that we can find a answer to your problem .
Good luck . Hugo