Never used a clicker myself but to the OP try that or hire a trainer (that's not a yank and crank guy) A prong collar is a tool that is easy to abuse!
I used one on my first dog and out of my three the one that I used the prong collar on was the only one that never walked a loose leash worth a crap!
No leash fine but not a loose leash.
Here's another option,
You could scan around You tube yourself fine something you like and come here for a second opinion.