Hi joe. That's a tricky one because when it comes to the systems of the square, John really is the man. Unfortunately that means he is a man in demand. Try him again and let him know you have a problem rather than in need of a service, and he may be more responsive (leave a voice message or send him a text). Hope that helps and good luck. ;o)
I have been relying on John for years and he is awesome, but this year he has been particularly hard to reach. The couple of times I managed to get trough him, he did not return my calls to confirm an appointment.