I had purchased Yonkers template for Joomla about two months ago. There has been no support from the developer (Created by Cocoon). The template is full of bugs and not compatible with latest Joomla version.
I’m sorry to hear you have encountered some issues with a theme.
I saw on the theme comments page that you already left a comment there for the author. If you also already emailed him and yet no reply, please also check the Spam folder, some emails from some email providers do go there accidentally, by default, unfortunately.
What can be done in case you still don’t receive a reply from the author:
Try to contact him on his official support website: https://createdbycocoon.com/support?envato_item_id=13411632
Contact Envato Help&Support Team and they will be able to help you with the dispute with the author. You can contact them by opening a help ticket here: Envato Help and Support
You can also apply a refund if the theme does not worked as advertised: https://themeforest.net/refund_requests/new
I hope it helps a bit
Thank you for your efforts.
I have created a final request. If that is not answered, I am planning
to go for refund.
I have checked the Spam folder and there is no mail from them.