I have taken him to many different classes in the past. I don't have the money to take him to one right now. The Petco class saw him on the prong and saw no reason to take it off him since he walked nicely on it.we mostly focused on reinforcing his sit and down stays and such. The other class I took him to was man's best friend and they used the prong so often it was never off
OK ... the first step in getting to the dog you is to "out think your dog!"
Had you gotten a "Boxer" your task would be easier, but alas you did not!
I have first hand experiance with the part in bold with my first (and thus far only OS WL GSD.) When Rocky and I had our "issues" he caught me off guard?? Pack fights ... before I got him ... I was an experienced dog owner more than ten years of experiance with real dogs! American Band Dawgs, Boxe/APBT and Boxers. SO a WL GSD ...no big deal ... yessss ... well ... not so much!!
What my did ...by "outthinking me" was exploit, things I had no knowledge of??? And round one ... "Pack Fights!!" I never experienced that?? Five freaking fights between Rocky and my Am Band Dawg! Rocky always started them .... freaking ticked me off! My wife was fried, the house was full of tension and it was like living with a freaking time bomb! The solution would have been more structure for him ... but at the time I was not "thinking" I was reacting to him. My wife was fried, Gunther was bearing the brunt of my lack of understanding ( and he handled it well) and I was pretty well ticked off!! I wound up in the ER, first stitches every ... breaking up a dog fight and to this day a permanently bent little finger! That was seven years ago and my little finger a constant reminder of the "cost of not out thinking your dog!"
Gunther passed following the last dust up due to unrelated issues so ... I was never able to solve that issue!!!
And now ... came round two!! H/A issues WTH??? He greeted company with a cold hard stare and a low growl ... WTH??? I'm a Boxer guy also and with my Am Band Dawg and my assorted Boxer and Boxers mixes ... I had never seen this?? Most likely with most owners ... yeah that's freakin it! Back to rescue and "PTS" you go! But "Rocky" and I got lucky because for me ... it meant "Pay Back!!" This crap ... shall not stand!!!
It"s another story but suffice to say, I solved it by "out thinking my dog!" And once I chose to "think" instead of react ... it was a problem that was actually astonishingly simple to solve. That was six years ago and Rocky .. is still here and doing just fine.
So that's a long way of "quoting my guy Jeff Gellman who often says "lady your dog is not that bad."
That said the "Clicker" thing?? I used to say ... they are crap! But that would be an overstatement but I do think it's fair to say ... that if you use a "Clicker??" You first have to "understand the tool" and then apply what you think you understand to your dog??? I think ... that's fair to say???
So ... your not the first to have problems with "proper understanding of a "Prong Collar." I got that tool wrong many years before you did!
But what I did was say "screw this" I won't use anything! Back to basics ... a Flat leash and regular collar it was and I got very good at it. I then went to a SLL and if you can walk a dog "properly on a flat leash and regular collar a SLL is "nothing!" Been there done that ... worked out fine.
That said ... back to basics .. the first video clip here "Doggie Dan" uses a Flat Leash and Regular Collar.
And ... fact of the matter is a "Prong Collar" should be an easier option?? If you are having troubles with it?? Then most likely you are doing something wrong?? A proper correction should be a "sideways" correction with a Flat Leash or SLL and it would only be a wrist flick sideways with a "Prong Collar." So most likely ... something is going wrong there.
At anyrate while this is my "SLL" it went sideways and I decided halfway thru it's not about a given tool it's more about the process. So Jeff Gellman, Sean O'shea and Tylor Muto are there and they all have Youtube clips that will help you understand how to better use a "Prong Collar."
Slip Lead leash - Boxer Forum : Boxer Breed Dog Forums
And ... you could also post a clip of you and your dog and folks on here could point out issues?? And that does not cost a dime! As I say ... "out think your dog."