Xmax value is not large enough despite the long voice coil

Hello,

I increased the magnets by 50% in my model, increased the voice coil by more than 100% and increased the top plate by 100% but my xmax value is about not much larger than before.

What could be the reason?
We have NO CLUE about dimensions of what you are using or magnetic circuit shape and values,you post neither images no numbers.
We need a crystal ball to answer.