Welcome ForceMajeure,
Don't let a bounce put you off, they happen, even to those of us who are experienced. Three things I do to minimize bouncing are: arrive to the runway threshold on speed, and at a suitable crossing altitude, then, I slow the plane before I allow it to contact the surface. If it's nice and slow, it'll be unlikely to bounce (much).
But, to the more important topic, your school must assure your progress with consistent training. Multiple instructor changes are counter to consistent. Yeah, stuff happens for instructors, but two or three should be the maximum for you throughout your training for a PPL. Seek assurance from the school of instructor consistency.
All pilots have times where they doubt themselves, or their progress through training. You would not have been sent solo, if you had not demonstrated adequate skill. Trust in their confidence in your skills to date, and continue....