Originally Posted by
deja vu
Change schools. You should not be having a different instructors every time.
I thouroughly agree. You should have consistency of instruction so that your instructor gets to know your weaknesses and finesses your flying skills. It's entirely acceptable to swap instructors if the one you're with isn't the right fit - some sort of personality clash, etc, but it's important to have a good instructor who can remind you of what you did right/ wrong last time and encourage change. Doing your PPL isn't just about Exercise Bashing and then doing your skills test. It's about finessing your flying and for that you need consistency of instruction.
As deja vu remarks - time to change schools for definite.