When I go to WoodMart > Header Builder the main pane is just a big empty square.
I have already updated the WoodMart theme, switched back to the parent theme, deactivated all 3rd party plugins, and cleared cache, and it’s still just empty.
To investigate further, I’ll need access to your server files — specifically the wp-content folder — since the issue can’t be resolved through the WordPress dashboard alone.
Please provide file manager or FTP access, so I can further check on your site and give you a possible solution.