Why were you linked to this page? I’m currently turning some of my premium themes into free ones – the one you pressed buy on is one of them. This process will take a while (probably months) to complete as the theme review queue on wp.org is long.
I don’t want users to buy a theme only to know that it has been released for free shortly thereafter, so it is currently unavailable. Stay tuned and you will be able to get your theme for free, once it passes the required quality-check on wp.org.
Thanks for your understanding,