Misbehavior of a seller

Hi, I’m asking for help because I can’t solve a problem with a poorly behaving seller.
Three months ago I reported a bug on the theme that blocks some native Wordpress features (everything related to custom post types does not work), and for several weeks he tried in every way to get me paid to fix the bug.
I managed to make him understand that he couldn’t ask me for money for something like that, and he said I would have to wait a couple of months.
It’s been three, and he still asks me to be patient.
In the meantime the theme has been removed, and I have reached the fifth out of six months of warranty.
What can I do?

Thanks to those who want to answer me

Hi,

Please open Help ticket and let them know.

Thanks

Thank you @mgscoder, I just opened it.

Marco