Well on the one hand it says you enrolled him in AN obedience class when he is younger and on the other hand it says you can't KEEP dumping money into classes and trainers.
What, exactly have you done?
He is at a quirky age and it sounds like some training issues and possibly lack of self confidence. You at least owe him finding someone knowledgeable (maybe ask if there is a schutzhund club nearby who can give you referrals) and work one on one with someone. They can also evaluate whether he is having a fear response or is just being a punk.
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