Seems I write a song and change the styles, after the song is saved if I try to change the style my style will not change. What is wrong? and how can I fix it?

Obvious possibility ... Have you checked that the tracks aren't frozen?

I made that same mistake yesterday on a song. I changed the style, clicked on generate and play and nothing changed. I immediately glanced at the screen and just as I expected, I had left all the tracks frozen from the previous style.

It's a easy mistake to make. I have done it in the past a couple of times.