Hello,
We have further checked this concern on your Site by enabling the Debug mode and found out that a third party Plugin TikTok was causing the conflict on your Site: https://snipboard.io/DOsuNj.jpg
When we deactivated that, the Single Product page was appearing fine by then. So, it is a third party Plugin conflict not a Theme end issue.
And according to the Envato Policy we don’t provide Support for the third party Plugin issues. You will need to contact the respective Plugin Support in this regard. They will guide you better.
Hope you can understand our limitations in this regard.
Note: Right now, the TikTok plugin is disabled on your Site so that you can see the difference.
Best Regards