First things to check. Make sure your camera is not animated and does not contain any keyframes in Blender.
If you have constraints set for the camera. The camera will snap back if the tween is outside the constraint. So make sure your constraints are large enough to allow the movement.
If you are using a collision material, make sure your tweens aren’t outside the collision material.
Without seeing the puzzles, I cant think of anything else off the top of my head that would cause a camera to complete a tween then snap back to the starting point. May want to look around for hidden camera puzzles laying under your existing puzzle blocks that could be executing?
Screen shot of your puzzles or if possible upload your project with blend and we can take a look.r